Question

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?

Answer 1

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

Answer 2

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.