>currently I don't have stereoscopic vision

>my brain CAN do it, if I had the correct images sent to my eyes somehow.

>when I watched Avatar, an actually well made 3D movie, it literally felt more real than reality

Buy an Oculus Quest 2. (Or any VR headset, but that's the best value at the moment.) It sends seperate images to each eye. You should get that same 'more real than reality' feeling. It may even train your eye muscles to see in 3D, I know I've seen some research into that area. (https://www.seevividly.com/ comes up on a Google search, though it seems to be prescription only)