I'll start with a basic explanation. print just shows the human user a string representing what is going on inside the computer. The computer cannot make use of that printing. return is how a function gives back a value. This value is often unseen by the human user, but it can be used by the computer in further functions.

On a more expansive note, print will not in any way affect a function. It is simply there for the human user's benefit. It is very useful for understanding how a program works and can be used in debugging to check various values in a program without interrupting the program.

return is the main way that a function returns a value. All functions will return a value, and if there is no return statement (or yield but don't worry about that yet), it will return None. The value that is returned by a function can then be further used as an argument passed to another function, stored as a variable, or just printed for the benefit of the human user.