Obviously there is no 'right' answer to this question. How many reps you'll use, how many rep ranges you'll use across the entire program, and other programming variables depend on many things.
But that said, many simple full-body plans have been built around squatting, benching, and pulling for heavy sets of 5. It works well because you get a nice blend of sufficient volume for hypertrophy, and sufficient intensity to teach you how to get tight and lift heavy weights. Look at something like Rippetoe's 'Texas Method' for an example of how to set everything up.