[Aakash]

Can I study college chemistry without the help of any teacher at home or school

but only using forum and good books?

can I study math and physics like this?

[Borek]

You can try. But first, without a feedback you will never know if you are making a solid progress, second, you need to be really motivated to spend some time everyday to learn.

Finally, if you are learning just for your own, that's OK, but nobody will believe you know something if you have no formal education - that is, some kind of a diploma.

[orgo814]

I think it's definitely possible... most chemistry textbooks nowadays come with a solutions manual with worked out problems so you can figure it out on your own. I feel like I've basically taught myself chemistry even with having a formal class since some of my professors have been so bad! However, the only way to tell if you really learned the material is to be evaluated by a qualified teacher and understand feedback. And as mentioned above, nobody is going to believe you know something unless you went through the formal process

[408]

Yes.

I studied chemistry both from books and home experiments before any formal chemical education beyond "this is the difference between a mixture and a compound" level.  It served me well when actually doing it in a formal setting as undergrad classes that were relevant to my personal interests were easy, and my synthetic technique ability was leagues above other undergrads.

It is entirely possible, but like Borek says, nobody will believe you unless you get the magic pieces of paper that society thinks determine knowledge or lack thereof.  If you think self study will get you a job, you are wrong in all cases except those with very lucky personal connections.