Yes, it can break up and clog both.
Yes
The clog is below the point where the toilet and the tub join the drain.
Yes, you can adjust the toilet clog to clause your toilet to overflow.
The toilet itself is plugged or the pipe from the toilet to the drain is plugged. It may be that the tub and sink have their own drain pipe that may connect to the main away from the toilet drain. Plunge the toilet or sometimes if you fill a 5 gallon bucket with water and pour it into the toilet as fast as it will take it, that will flush out the line. It is a greater amount of water all at once an forces out what the clog is.
You didnt specify where the clog is located. So, if you are referring to a bathroom sink clog, Liquid Drano really works well for me. For a toilet, most clogs can be removed with the use of a plunger. But if this is a drain in a utility closet, then you may have to contract a professional plumber who a access to device know as a Drain Snake to breakthrough the clog for you.
There may be something that is partially blocking the drain.
Yes, hair is one of the hardest things to clean out of a drain, maintance man.
another clog, further down the drain pipe. You need a drain snake.
All toliet paper can clog a toliet...just dont use half of the roll good toilet melts in water
Not unless a handfull goes in at the same time. Even then, there probably would not be a problem. One or two at a time is not a problem.
A lot does, but not a little. A lot of artificial hair can clog a toilet a bit more than human or animal hair.