If sin can't exist in Heaven, how was Lucifer able to commit sin when he lived there? God sent him out of Heaven and created hell for him?

Hmm are you trying to be clever ?

Irrespective, before Lucifer sinned, he lived in heaven. The moment he sinned he was cast out. Where's the problem with sin not existing in heaven exactly?

as soon as lucifer rebelled he was immediately cast out of heaven to the earth. hell is the prison house where most angels are chained up until the great white throne judgement. god owns hell not satan.

the angels made a choice to rebel. once they made that choice and committed the action god immediately cast them out of heaven. no sin will be tolerated in heaven

You really need a good Bible study, if this is what your religions has taught you.

And in Job chapter 1 satan still has free access to heaven and is present along with a bunch of other angels.

"..6 One day the angels[a] came to present themselves before the Lord, and Satan[b] also came with them. 7 The Lord said to Satan, “Where have you come from?” Satan answered the Lord, “From roaming throughout the earth, going back and forth on it.”

fairy tales don't have to make sense....

Um, freewill? But if you really study both those instances they were all on earth when the rebellion took place. Lucifer was in the Garden of Eden and the angels were with earth women.

Because the fictional story of that deity and of it's minions is really BADLY thought out and written.

"Properly read, the Bible is the most potent force for atheism ever conceived." Isaac Asimov