you can get by, just about on benefits. you can even order food online and have it delivered so you would never have to leave your house... it's probably not very helpful if you are looking for a cure for social anxiety though.
working from home doesn't really work out unless you have a specific type of thing you can offer others, like if you have your own business. but that presents a lot of social interaction as you will be the face of the company and as such have to deal with customers or other people you do business with directly. you also need to have a sort of personality that is very self reliant, enterprising, entrepreneur and skilled in organisation or hire someone to work that part of the business,which will mean some degree of interactions. promotion of what you offer might be necessary too ,which also requires social work. sure, you can be a one man business and never speak to a person at all or keep it to a very bare minimum, or at a pace which is more comfortable for you in light of your mental health problems, but I think it would severely impact your work and have detrimental consequences.
I don't really think there are jobs for the average person working as part of an existing business from home. most are skilled or specialized and require training. that's fine if its something you are really interested in, but for a lot of people they don't want to train to do something don't have much interest in but simply go for because it works around their limitations. a lot of people want to use what skills they have to their advantage, its a bit of a depressing scenario if you are simply lumping for a career job direction because you are hampered down by your mental health restrictions.