If I use my personal hotspot to go on movie star planet will I use data?

I have a iPhone 4 with verzion

Ofcourse, if you use the internet you're using data, but I'd recommend you use Hotspot Shield, it gives you the privacy of a VPN AND heavily cuts down data usage on your mobile internet plan, saving you money and data. Hope this helped!

Oh yeah for Hotspot shield just google it and download it it's only a few Megabytes but can save you Gigabytes of data.