What's the difference between "qué" and "que" in spanish? also why in some cases does "qué" in a question mean "how" instead of "what" and how can i know which meaning they're trying to say?

Qué usually in an exclamation usually means How? Or What? que usually means "that" depending on the wording of the sentence. There are also marks with the lettering that should help you when the words are spelled the same way like: que and qué, or Dias and Diás.

I hope I helped a bit. I'm learning Spanish myself too.

It really just depends in the sentence you use it in. For example
Que andas haciendo?/ What are you doing?

The answer is a it says that he/she will practice the interview in third head