I know this question looks like a duplicate but it's not, all the other solutions are not working for me.
I'm using debian 10 buster and I installed texlive with:
sudo aptitude install texlive texlive-base, then I tried to compile a document and got this error:
Package babel Error: Unkown option `french'. Either you misspelled it or the language definition file french.ldf was not found
Next I tried this:
tlmgr install babel-french
but I got this error:
tlmgr: Remote repository is newer than local (2018 < 2019) Cross release updates are only supported with update-tlmgr-latest(.sh/.exe) --update