Why there are more than one verb in this sentence?

You will have classes with the rest of your House, sleep in your House dormitory, and spend free time in your House common room.

This is a three-element list, and in lists, you only put a conjunction before the last element.

The author could have written this:

You will have classes ..., you will sleep ..., and you will spend ....

However, when the subject (you) is the same for each element of the list, we don’t need to repeat it. We can do the same with verbs, even a helping verb (will) attached to different main verbs (have, sleep, spend).