How to add other language keyboards to the login page

Hi,

I have two Ukranian refugees and tried to change the language of the keyboard to Russian for them to use it for home schooling. I had to delete all the other keyboard to make this work. Then I restarted and when needed to enter the password, since the Russian keyboard doesn't have latin characters, I can't type the password. I should have removed the password before restarting. Is there any way to fix the issue?

Thanks a lot,
Torsten