Nothing here is said about man having the ability to come to Christ, read Jn 6 44 65
Clearly the ability to believe Christ is here
John 6:45 (NASB95) — 45 “It is written in the prophets, ‘AND THEY SHALL ALL BE TAUGHT OF GOD.’ Everyone who has heard and learned from the Father, comes to Me.
This is true even if God's teaching is through another party
For example those who believe Moses would believe on Christ
John 5:46 (LEB) — 46 For if you had believed Moses, you would believe me, for that one wrote about me.
Belief in the words of others as well
Acts 14:1 In Iconium they entered the synagogue of the Jews together, and spoke in such a manner that a large number of people believed, both of Jews and of Greeks.
Acts 18:8 Crispus, the leader of the synagogue, believed in the Lord with all his household, and many of the Corinthians when they heard were believing and being baptized.
John 1:6–7 (NASB 95) — 6 There came a man sent from God, whose name was John. 7 He came as a witness, to testify about the Light, so that all might believe through him.
Acts 8:12 But when they believed Philip preaching the good news about the kingdom of God and the name of Jesus Christ, they were being baptized, men and women alike.
Acts 2:37–38Now when they heard this, they were pierced to the heart, and said to Peter and the rest of the apostles, “Brethren, what shall we do?” Peter said to them, “Repent, and each of you be baptized in the name of Jesus Christ for the forgiveness of your sins; and you will receive the gift of the Holy Spirit.
Even what is written is sufficient
John 20:30–31 Therefore many other signs Jesus also performed in the presence of the disciples, which are not written in this book; but these have been written so that you may believe that Jesus is the Christ, the Son of God; and that believing you may have life in His name.
Acts 17:11–12 Now these were more noble-minded than those in Thessalonica, for they received the word with great eagerness, examining the Scriptures daily to see whether these things were so. Therefore many of them believed, along with a number of prominent Greek women and men.