Answer 1

in short prefix ++x means that u add 1 to x then read value of x and x++ means that u read the value of x and then add 1.
when I first heard about prefix and suffix I thought my brain was gonna melt and I could not see any benefits, except for x++ but now I'm trying to code myself and realized that they are very useful.
believe me when I say. don't try to wrap your head around this, let it sink in on it's own time.
just start with the easy and the one that u understand. As u evolve as a programmer u will understand the need and benefits of prefix and suffix.