Didn't you say you are only 20 years old? You have a long time to go and it's too early to give up and declare defeat. If you want to see a long early life of failure check out Abraham Lincoln's life.
All jobs require interaction with other people. Even stay at home jobs require that you sell your product to someone or work for a company that gives you work. You will always need people to give you money no matter what you do.
I suggest you look around for people that you would like to be like and try to imagine how they got where they are and how you can model yourself after them. Plenty of managers have bad tempers, but they probably have more education than you do and worked hard to get where they are. They didn't give up at 20. I suggest you check our books and recordings by motivational speaker Tony (Anthony) Robbins to get you started. You can Google the name and check around for used copies of his work on Ebay, Half.com and Amazon. Some libraries will also have it on hand, especially in their job search section.