If you need help understanding compiler diagnostics, please post the exact diagnostic messages.
No need to start over, but there are a number of things you need to fix:
Here are the problems I see:
cout << void LengthofTime(int time) << void MrSmith() << "Running time" << int RunningTime(int time) << "minutes." << endl;
You can call functions in a cout statement as long as the function returns something cout understands. You can't however call a void function in a cout statement since it doesn't return anything. Also, when you call a function in a cout statement, you don't include the type of the function. The compiler knows the type of function from where you declared it.
void LengthofTime(int time)
void int time = 100
Not sure what you're tring to do there. You can't declare a variable between the function header and the opening brace. Also
makes no sense.
Line 18: I don't understand what you're trying to do with the switch statement.
Line 28: You're trying to return y, but y is not defined. Also, LengthOfTime is declared as a void function, so it's not legal to return anything.
int RunningTime(int x)
int x = answer
Again the same problem trying to declare something between the function header and the opening brace.
PLEASE USE CODE TAGS (the <> formatting button) when posting code. It makes it easier to help you.