How do they relate to Jesus?
Signs are to prove to the Jews that whoever that is speaking to them is indeed sent by God.
Since Jesus claimed to be the Son of God, he was given signs and wonders for Israel to verify his identity. He did more signs and wonders than Moses, Elijah and anyone else.
John wrote his gospel as a record of the 8 signs that Jesus performed in order for Jews to believe that he is their promised Messiah (John 20:30-31).
In that record, the signs are seen as works of God. There are at least two times the John account explains that.
John 10:
24 Then came the Jews round about him, and said unto him, How long dost thou make us to doubt?
If thou be the Christ, tell us plainly. 25 Jesus answered them, I told you, and ye believed not:
the works that I do in my Father's name, they bear witness of me.
John 14
10 Believest thou not that I am in the Father, and the Father in me? the words that I speak unto you I speak not of myself: but the Father that dwelleth in me, he doeth the works. 11 Believe me that I am in the Father, and the Father in me:
or else believe me for the very works' sake. 12 Verily, verily, I say unto you, He that believeth on me, the works that I do shall he do also; and greater works than these shall he do; because I go unto my Father.
Notice the Jews are not expected to accept Jesus as the Son of God "by faith"? They require a sign, as Paul explained later in his epistles.
But for us now in the Body of Christ, we are not to seek after signs and wonders. We believe in the gospel of grace by faith, not by sight.