Just I'm looking for Specific On/Off Firewall ?

hello,

I use the internet alot, but I limit my use when I’m out without wifi and using mobile data. (Most places you visit here don’t have wifi and even landlines are so rare that even businesses don’t have landlines and common data plans only last for 1-3 days so very limited data)

So I need a program that literally blocks everything unless I hit the “On” switch.
So an antivirus or internet protection of any kind is NOT needed but rather something that protects my bandwidth if you know what I mean.
As soon as my laptop connects to my phone’s wifi hotspot, it becomes a hungry beast that hasn’t eaten for days.

Please help.
Thanks!

I didn’t find the right solution from the Internet.

References:
https://www.bleepingcomputer.com/forums/t/658874/looking-for-specific-onoff-firewall/

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