Lines 16, 17, and 18: you declare 3 variables and don't initialize them, exactly as the compiler is probably telling you.
16 17 18
int myHeight = 0;
int feet = 0;
int inch = 0;
Also, lines 17 and 18 aren't doing what you think they're doing. You're actually declaring 2 ints, one named feet, the other name intInch. I think you meant to say it the way I have it in my example above. Line 17 ending with a semicolon and line 18 actually declaring an int variable named inch.
I should have said that the problem is in how i'm declaring or calling something. Because i get to the results and it shows
x centimeters is equal to
0 feet 0 inches
You're using the global variable int myHeight; and then selectively hiding it by redeclaring it in some of your functions. You don't need global data for this. Remove line 11.