I am over 50 gB on my T-Mobile unlimited plan this month. (HINT HINT) they tell me if Im on a congested tower they may de-rate my service a bit (And so they did for about 5 minutes) but I get 10 GIG high speed to other deivces, after that they throttle to about 110% of "Full Speed" on the tower I'm using now (Meaning I don't notice on this tower, I do on other towers) and 50 Gig full speed to phone (or less depending on tower) and I may get downgraded to Edge if tower is very busy.
On your non-Cellular devices (Your comnputers) make sure to mark the Wi-Fi connetion to the hot spot as A METERED connection how to do this depends on your wi-fi adapter software...
On a Chrome book I do not see a way to do this. Been a while since I did it with Widders (windows) That way UPDATES will not download.. They can eat up a couple hundred Megs (or more) very very fast.