It's £119 to buy it outright, which is supported till 2029 I think . So from now would work out approx £30 a year (or £2.50 a month equivalent) - which I don't think is too bad. Other than that I have only used Libre office, and Abiword. If you just want a word replacement, and not full office, you could try abiword. There's also a portable version. OR you could just use Wordpad

It's possible to install it on Windows 11. Personally I'd rather buy the real Word outright.
I can't see what the difficulty was with uninstalling libre office either it should just uninstall normally and no need to reinstall Windows. However I did have to reinstall Windows to completely uninstall a "cheap" copy of MS Office Professional Pro Plus 2021 - which was a total pain and why I next bought the full price version of Ms Office Home from the Microsoft store.