help what do I do?

I finally got the stray that I've Bern feeding and caring for for the past weeks to come inside
I'm trying to make him an inside cat
(I don't like inside outside cats and outside cats because they can get hurt or mistaken as strays) the stray I've taken in used to have a home judging by the way he adjusted but he's wanting back outside I already put a collar on him what do I do does he just need more time adjusting is that why he still wants out after being inside for a while

He may be wanting out just to do his business.  If you use Dr. Elsey's Cat Attract litter to start out with, he will be drawn to it.  He may continue to want to go out but you should probably not allow that for awhile until he has relaxed into being an inside cat.   My friend has a cat she brought in from the outside, and she has harness trained her and they go on walks every night around the neighborhood.  It didn't take long to train her because she wanted to go out and check out all her old territories, so my friend let the cat lead, and now she trots right out like a dog.  If she misses her walk for a few days due to inclement weather, she starts getting grumpy!  Outside cats can become quite bored inside, so you may want to get some toys and play with him, something like DaBird and the laser pointer that he can chase.  Setting up a bird feeder outside a window and a place for him to watch it is also a good idea.

he plays sorta but mostly gives me that what in the check are you doing look .. but at least I know he's playful kinda

If he isn't neutered, he may insist on going outside because he's looking for love.  Otherwise, he's used to being outside, so it may take him awhile to make the complete adjustment.

Thank you for helping him.  Have patience - he'll adjust soon enough.