I started self learning mathematics and physics .. but the thing is I can't join a college , but I watch online lectures and read textbooks instead .. I am interested in theoritical physics .. But I dont know if working on theories without formal education in a college accepted or not?
There are far more journals than there used to be, and getting a paper accepted by one of them is far easier than it used to be. But this is because many journals now are low-quality. Even with a degree it is not necessarily easy to get published in a top-quality journal.
Fair warning though, the barrier to entry is hard, and there's a good chance you won't be able to find anything worth publishing as a self-educated physicist. There's a reason why the traditional path to research is by doing a PhD - it's a skill you need to learn, and something that is best learned from someone experienced (i.e. a professor).