I am sorry to read of your situation.
We cannot bargain with God to obtain a miracle.
This life is temporary, whatever the state of our health.
For God to hear us, we must be in covenant relationship with him by obeying the gospel preached by Jesus Christ.
John 14:6… I am the way, the truth, and the life: no man cometh unto the Father, but by me.
Jesus Christ gave his life that we might have forgiveness for sin.
The Gospel preached by Jesus and his apostles promises resurrection from the dead to eternal life in the kingdom of God.
If we want this, we have to obey the gospel.
There are no short cuts.
In order to be in covenant relationship with God, we must:
1. Understand and believe the gospel.
2. Repent of our sinful way of life.
3. Be baptised by immersion in water for the forgiveness of past sins.
Acts 2:38… Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins…
Acts 22:16 And now why tarriest thou? arise, and be baptized, and wash away thy sins, calling on the name of the Lord.
4. Live a new life.
Romans 6:4 Therefore we are buried with him by baptism into death: that like as Christ was raised up from the dead by the glory of the Father, even so we also should walk in newness of life.
This new life must be lived by the commandments of Christ.
John 15:14 Ye are my friends, if ye do whatsoever I command you.
Matthew 28:20 Teaching them to observe all things whatsoever I have commanded you:
After baptism we will still sin, but providing we are making a determined effort to live by the commandments of Christ, we are promised forgiveness of sin by confession in prayer.
1 John 1:7 But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin. 9 If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness. 10 If we say that we have not sinned, we make him a liar, and his word is not in us.
When we are baptised into Christ we are in a covenant relationship with God and can approach God through Christ to find grace to help in time of need.
Hebrews 4:16 Let us therefore come boldly unto the throne of grace, that we may obtain mercy, and find grace to help in time of need.
1 John 5:14 And this is the confidence that we have in him, that, if we ask any thing according to his will, he heareth us:
It may not be God’s will to restore us to health in this life.
2 Corinthians 12:9 And he said unto me, My grace is sufficient for thee: for my strength is made perfect in weakness. Most gladly therefore will I rather glory in my infirmities, that the power of Christ may rest upon me.
But we have the comfort of hope in the life to come.
Revelation 21:4 And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away.
I hope you find this helpful.