Tethering lets the Android device to share the PC's network and Internet access. Hotspot does it the other way around. You set it up in the Android device and the PC connects to that.
The down side of that is when your free mobile data runs out, phone costs rocket and you do not want the PC to download Windows Updates while on a Hotspot you're paying for,.
I just need on line for a short time to file my taxes, I already completed using my phone, it won't let me file. Went round and round with IRS, they don't know. All I can think of , is it won't work on my phone. So if I can get my pc going , hopefully that will doit. Just having troubles ,getting it to hotdpot.