as a massive tldr - the only language to be used in government and government-adjacent institutions is to be exclusively ukrainian (and since its a cis country, schools are also a part of the government). everything else is not affected. there are also regional self-sufficiency laws relating to minorities that basically mean that if you pull in enough votes you can actually get funding from the government to reinstate russian teaching in schools. and that basically means that nobody fucking cared and the faggots seething are trying to pull a sham.
Ukraine