Both latin and cyrillic fonts

Hey there,

I’ve been trying to find an existing font that applies both to latin and cyrillic letters. Unfortunately, it is just a couple of them and they are horrible.
Is there any way I could install some new fonts. I’ve been looking for a resolved topic, but most of them are too old, and it seems I have other php files and code, can’t find anything.

PS: preferrably an option without a Child’s Theme. Because I tried to fix it, and it doesn’t work as it should, a bit too advanced for now…:/