Many instances are mixed language. Feddit.org for example is mainly German communities for now but is officially a German/English instance and one of the largest communities is c/Europe, which is in English. Blocking whole instances will block many English communities as well. Though I get that that might be an acceptable trade-off to get rid of a flood of posts you don’t understand.
It’s a shame the language selection doesn’t work on many apps.
I would never paste code into a Word document. I use Notepad++ for that.