Since it is so difficult to look it up for yourself, here is the answer already hinted at:
[Rom 9:19-26 KJV] 19 Thou wilt say then unto me, Why doth he yet find fault? For who hath resisted his will? 20 Nay but, O man, who art thou that repliest against God? Shall the thing formed say to him that formed [it], Why hast thou made me thus? 21 Hath not the potter power over the clay, of the same lump to make one vessel unto honour, and another unto dishonour?
22 [What] if God, willing to shew [his] wrath, and to make his power known, endured with much longsuffering the vessels of wrath fitted to destruction: 23 And that he might make known the riches of his glory on the vessels of mercy, which he had afore prepared unto glory, 24 Even us, whom he hath called, not of the Jews only, but also of the Gentiles?
25 As he saith also in Osee, I will call them my people, which were not my people; and her beloved, which was not beloved. 26 And it shall come to pass, [that] in the place where it was said unto them, Ye [are] not my people; there shall they be called the children of the living God.
Your question was anticipated two millennia ago and answered by Paul. Do you have any specific questions, or merely object to God being “unfair”?
I'm not sure proving we had free will was the point, since what we learned from the fall was vastly more - about God's love, his mercy, about ourselves - things we could have learned otherwise from what means? Even the angels are learning per scripture.
