All we know about Paul (originally named Saul) is what we read in the Acts of the Apostles and the letters. Saul was a Pharisee and we first encounter him at the stoning of Stephen.
Acts 7:58 And cast him out of the city, and stoned him: and the witnesses laid down their clothes at a young man’s feet, whose name was Saul.
Acts 8:1 And Saul was consenting unto his death. And at that time there was a great persecution against the church which was at Jerusalem; and they were all scattered abroad throughout the regions of Judaea and Samaria, except the apostles.
Saul actively persecuted the Jews in Jerusalem who believed in Christ.
Acts 8:3 As for Saul, he made havock of the church, entering into every house, and haling men and women committed them to prison.
He set out to persecute the believing Jews at Damascus
Acts 9:1 And Saul, yet breathing out threatenings and slaughter against the disciples of the Lord, went unto the high priest, 2 And desired of him letters to Damascus to the synagogues, that if he found any of this way, whether they were men or women, he might bring them bound unto Jerusalem.
He says of himself, explaining his conversion:
Acts 22:3 I am verily a man which am a Jew, born in Tarsus, a city in Cilicia, yet brought up in this city at the feet of Gamaliel, and taught according to the perfect manner of the law of the fathers, and was zealous toward God, as ye all are this day. 4 And I persecuted this way unto the death, binding and delivering into prisons both men and women. 5 As also the high priest doth bear me witness, and all the estate of the elders: from whom also I received letters unto the brethren, and went to Damascus, to bring them which were there bound unto Jerusalem, for to be punished. 6 And it came to pass, that, as I made my journey, and was come nigh unto Damascus about noon, suddenly there shone from heaven a great light round about me. 7 And I fell unto the ground, and heard a voice saying unto me, Saul, Saul, why persecutest thou me? 8 And I answered, Who art thou, Lord? And he said unto me, I am Jesus of Nazareth, whom thou persecutest. 9 And they that were with me saw indeed the light, and were afraid; but they heard not the voice of him that spake to me. 10 And I said, What shall I do, Lord? And the Lord said unto me, Arise, and go into Damascus; and there it shall be told thee of all things which are appointed for thee to do. 11 And when I could not see for the glory of that light, being led by the hand of them that were with me, I came into Damascus. 12 And one Ananias, a devout man according to the law, having a good report of all the Jews which dwelt there, 13 Came unto me, and stood, and said unto me, Brother Saul, receive thy sight. And the same hour I looked up upon him. 14 And he said, The God of our fathers hath chosen thee, that thou shouldest know his will, and see that Just One, and shouldest hear the voice of his mouth. 15 For thou shalt be his witness unto all men of what thou hast seen and heard. 16 And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on the name of the Lord. 17 And it came to pass, that, when I was come again to Jerusalem, even while I prayed in the temple, I was in a trance; 18 And saw him saying unto me, Make haste, and get thee quickly out of Jerusalem: for they will not receive thy testimony concerning me. 19 And I said, Lord, they know that I imprisoned and beat in every synagogue them that believed on thee: 20 And when the blood of thy martyr Stephen was shed, I also was standing by, and consenting unto his death, and kept the raiment of them that slew him.
He writes to the Philippians:
Philippians 3:4Though I might also have confidence in the flesh. If any other man thinketh that he hath whereof he might trust in the flesh, I more: 5 Circumcised the eighth day, of the stock of Israel, of the tribe of Benjamin, an Hebrew of the Hebrews; as touching the law, a Pharisee; 6 Concerning zeal, persecuting the church; touching the righteousness which is in the law, blameless. 7 But what things were gain to me, those I counted loss for Christ. 8 Yea doubtless, and I count all things but loss for the excellency of the knowledge of Christ Jesus my Lord: for whom I have suffered the loss of all things, and do count them but dung, that I may win Christ, 9 And be found in him, not having mine own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of God by faith: 10 That I may know him, and the power of his resurrection, and the fellowship of his sufferings, being made conformable unto his death; 11 If by any means I might attain unto the resurrection of the dead.
Paul went from persecuting the Church to becoming the ‘apostle to the Gentiles’. He received the gospel and Holy Spirit powers directly from Jesus himself.
1 Corinthians 11:23 For I have received of the Lord that which also I delivered unto you, That the Lord Jesus the same night in which he was betrayed took bread....
1 Corinthians 15:3 For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures
Galatians 1:12 For I neither received it of man, neither was I taught it, but by the revelation of Jesus Christ. 13 For ye have heard of my conversation in time past in the Jews’ religion, how that beyond measure I persecuted the church of God, and wasted it: 14 And profited in the Jews’ religion above many my equals in mine own nation, being more exceedingly zealous of the traditions of my fathers. 15 But when it pleased God, who separated me from my mother’s womb, and called me by his grace, 16 To reveal his Son in me, that I might preach him among the heathen; immediately I conferred not with flesh and blood: 17 Neither went I up to Jerusalem to them which were apostles before me; but I went into Arabia, and returned again unto Damascus. 18 Then after three years I went up to Jerusalem to see Peter, and abode with him fifteen days. 19 But other of the apostles saw I none, save James the Lord’s brother. 20 Now the things which I write unto you, behold, before God, I lie not. 21 Afterwards I came into the regions of Syria and Cilicia; 22 And was unknown by face unto the churches of Judaea which were in Christ: 23 But they had heard only, That he which persecuted us in times past now preacheth the faith which once he destroyed. 24 And they glorified God in me.
He endured suffering for his belief.
2 Corinthians 11:22 Are they Hebrews? so am I. Are they Israelites? so am I. Are they the seed of Abraham? so am I. 23 Are they ministers of Christ? (I speak as a fool) I am more; in labours more abundant, in stripes above measure, in prisons more frequent, in deaths oft. 24 Of the Jews five times received I forty stripes save one. 25 Thrice was I beaten with rods, once was I stoned, thrice I suffered shipwreck, a night and a day I have been in the deep; 26 In journeyings often, in perils of waters, in perils of robbers, in perils by mine own countrymen, in perils by the heathen, in perils in the city, in perils in the wilderness, in perils in the sea, in perils among false brethren; 27 In weariness and painfulness, in watchings often, in hunger and thirst, in fastings often, in cold and nakedness. 28 Beside those things that are without, that which cometh upon me daily, the care of all the churches. 29 Who is weak, and I am not weak? who is offended, and I burn not? 30 If I must needs glory, I will glory of the things which concern mine infirmities. 31 The God and Father of our Lord Jesus Christ, which is blessed for evermore, knoweth that I lie not. 32 In Damascus the governor under Aretas the king kept the city of the Damascenes with a garrison, desirous to apprehend me: 33 And through a window in a basket was I let down by the wall, and escaped his hands.
During his ministry, he made three missionary journeys, establishing churches in various places. He also wrote letters to the churches clarifying the doctrines associated with the gospel. He was imprisoned and taken to Rome where he eventually died. His death is not recorded in the Bible.
I hope you find this helpful.