Hi there.

If you cannot afford any coaching, then you will have to study at home . And you have disturbances then study at night . Midnight actually. And watch YouTube videos to understand your query. 

And solve previous year questions. But most importantly , do not give up . 

well, we can understand your situation, accoding to your family situation the right thing which we recommend you is to find a place where you can have peaceful mind and find the efficient time in the studies, as you have mentioned that the financial conditions of yours is low so it is appropriately better  to study at home and then try to spend more time on the studies controlling all yourself and find the path suitable for you,, hope you got my answer, all the best.