Why? Why can't God enable humans to have free will without suffering?
Purposes that are completely determined by God, and could easily be changed by God.
That's not the question. How do you not understand the issue is with why a loving ALL-POWERFUL being would choose to make a world in which suffering was a necessary part.
I don't want to curse or praise anything, I just want you to acknowledge an obviously nonsensical position.
I think it's simple from many different perspectives. Let's try this on for size:
Free will is understood as the freedom to live in society. Once someone misuses their free will for evil, best practice is to restrain/retrain them. Murderers in prison, non-murderers roaming free.
This aligns with concepts of Heaven and Hell. Those able to be morally perfect can live in utopia, free, the immoral will be where they can harm no other persons or creatures.
This aligns with suffering. Some suffering is beneficial--lifting weights for muscles, struggling to learn a new athletic activity or memorize facts for tests, some suffering is caused by using free will for evil.
I'm not God, I'm not as moral as God. True free will allows me to disobey orders, from God, the original sin of the Garden being disobedience. I think morally imperfect creations don't have free will unless they can choose between good and evil, not good and good which is not a choice, and not good vs. lesser good--which lesser good is relatively evil!
I like your question, but part of the answer is neither you nor I can copy ourselves, and I don't think infinite God can make more infinite gods--all His creations are shadows of him, just like all our creations. It's not free will if I can't choose to do the wrong thing, even "the lesser good" is not absolute good. If I only have one choice in every moral situation--the highest good--I don't have free will. Free will is not choosing between one option. There's no "between"!
You are asking a question analogous to, "Why can't I eat only pizza but freely choose what food I eat?" or "Why can't God make a rock too heavy to lift?" when He's already had to move the mass of the rock to time/space to create it or "make" it!
God doesn't do anything illogical. The question is illogical and moot IMHO.
As for the other question you raised, "why must there be suffering", you are begging questions--I say so respectfully--including one with a presupposition about suffering being unneeded or without purpose. The Bible address this question, by the way, and gives over 30 legitimate purposes for suffering--you may not like it, but the 30 reasons are mainly blessings on God's people:
Romans 8:28 says, "And we know that all things work together for good to them that love God, to them who are the called according to his purpose." Note here--if I suffer in this life, I get rewarded in the next. If you suffer, could it be meant as a wake-up call for repentance or to seek faith? Note, that's different than an innocent child suffering, and the Bible addresses that differently, rather than put all suffering under a "God must be stupid or cruel" banner, but the fact that you and I believe children are INNOCENT means we know adults must be GUILTY before God.
It's logical, if God should be held accountable for making innocent children suffer, why He is unjustified in making non-innocents suffer, if that suffering is proportionate to their sin lives? Ouch. But some suffering which SEEMS meaningless has MUCH meaning--time to read that Bible!