There are various websites that resell MSDNAA keys for 2 Euros or so[1].
I got a Win11 Pro and Office 2021 Pro for dirt cheap there, the keys worked (after a phone activation IIRC), and haven't had any problems so far. Without access to such prices I would have switched to Linux and LibreOffice already as there's no way I can pay full retail prices for those.
Beware this is a legal gray area, I'm not affiliated, not endorsing this practice, and not responsible for your outcome. I assume Microsoft is aware of these practices but turns a blind eye as that just means more users into their ecosystem anyway, so why ruin the party.
You can still use a program like Sandboxie to try to sandbox an application.