To declare a variable, write the type followed by the name: int count;. This creates a variable but does not give it a value yet. You can initialize when you declare: int count = 0;.
This is safer than declaring without initializing because you know the starting value. You can declare multiple variables at once: int x, y, z; or int a = 1, b = 2;. I recommend one per line for clarity in larger programs.