How to fully switch to English?

Question

linux

Yesterday, all evening I sat and changed the language of the system. Left only the English locale through localepurge. The language has changed everywhere. But I still see in locale -a what is ru_RU, and now there are question marks in the terminal (as I understand it, this is Russian). How to FULLY switch to English? So that even the terminal gives out only English texts.
I have already renamed the system folders, but with the exception of the Desktop, for some reason it does not allow itself to be renamed and simply creates a new folder with the name Desktop.
debian 9 xfce

Answer 1

1 , 2 .