What do you call a person who takes everything literally?
A literalist is one that engages (from Merriam-Webster) in literalism, adherence to the express substance of an idea or expression. https://english.stackexchange.com/questions/173651/is-there-an-expression-for-someone-who-often-takes-things-too-literally/173652#173652.
What is a Sophomaniac?
sophomania (uncountable) A myth of getting awesome intelligence.
What do you call a person who can do many stuff?
flexible. To describe a person or thing that may adapt to do many things or serve many purposes, consider the adjective flexible.
What do you call a person who acts like they know everything?
adjective. somebody who is conceited behaves in a way that displays they think they are very clever, skillful, or sexy.