What are some jobs you could be self-employed and not need to hire people or have co-workers and it's not necessary but could you please list some mean salaries too?

What are some jobs you could be self-employed and not need to hire people or have co-workers and it's not necessary but could you please list some mean salaries too?
Not many come to mind. Freelancers of various types are the main ones: writer, private investigator, piano tuner, hair stylist, small contractor, caregiver.

Even at that, you may have to work with people. A plumber or electrician has to work with contractors and/or deal with customers directly. A writer has to get article assignments and go out and interview people and do research. (Forget writing best-sellers. Not one in a million is going to succeed at that.) Hair stylists typically rent stations in a salon and work alongside their peers, even if not as co-workers.

Sorry to break the news, but there is no such thing as a salary when you are not working for someone. When you sign on with an employer, you get regular pay. When you work for yourself and alone, without employees, you do work for hire and you charge by the job. No work, no pay. You may have to work through an agency and pay agency fees. And you have to spend a certain amount of time seeking work (selling your services) and a certain amount managing the business: keeping track of appointments, keeping your books, paying taxes, maintaining licenses.

Your pay is going to depend both on what you do and on how often you do it. If you have to spend a lot of time hustling jobs, you are spending less time working. If you are not hustling jobs, you are probably not getting them. Going rates will be affected by factors of all kinds, from the type of work to the area you are in to how good you are at it. There is no way to give an average. Go find someone who does the kind of work you want to do and see if he or she is willing to talk to you.