Hotspot [Q]

Hey sorry for a noon question but I never been on T-Mobile and I've never used hotspot as much as I'm bout to use it this school year. I have the 5GB data plan on T-Mobile using the hotspot on CM 12.1 I know its free hotspot because of the root automatically but I was wondering does it use up the 5GB in my plan? Sorry if the answer is very simple I need to know to prevent extra charges