Thank you for your question.
The Bible indicates that Jesus had both brothers and sisters. Here
Mark 6:3 Is not this the carpenter, the son of Mary, the brother of James, and Joses, and of Juda, and Simon? and are not his sisters here with us? And they were offended at him.
Jesus’ antagonists were trying to undermine Jesus’ authority by speaking of his family.
Additionally we know that the name of one of his brothers was called ‘James’ because Paul makes mention of this:-
Galatians 1:19 But other of the apostles saw I none, save James the Lord‘s brother.