Do you think everything would have been perfect if there’s no free will? God will never create or do anything evil, only other’s free will it can be done? But doesn’t God have free will himself?
Well for one thing, there would only be three people in existence if no one but God had free will. God dicided to make people like himself rather than mindless puppets.
God created everything, and it is him who decided what is good, and what is evil. You are correct that he does no evil, and that his creatures can and did do evil by rebeling against him.
He does indeed, and he both authored goodness and chose it from eternity. Why would he choose the evil he hates?
God’s will is always singular, with no need of choice, being moved by singularly perfect wisdom. The human will is always inferior to His, being informed by less-than-perfect wisdom-unless and until it puts its trust in Him.. The finite must recognize its limitations and come to rely on the Infinite. In any case free will was a good gift given to man by God. The* abuse* of free will, first of all by rejecting God’s authority, is an essential ingredient of sin.
The misuse of free will is sin. Free will is not the ability to do what you want, but the ability to do what you ought. God created a moral universe. Such a universe would hardly be perfect without beings with free will.
Others have addressed your specific questions.
The Catechism states that:
[quote=CCC]1873 The root of all sins lies in man’s heart. The kinds and the gravity of sins are determined principally by their objects.
Free will is simply the capacity to decide for oneself what is good, even if it is contrary to God’s will.