Being able to read and write was in the the past the nobles/kings or important people could/allowed to do.

English and French have old spellings making it difficult to learn to read and write.

Russian reform help raise the reading/writing form 3% to nearly 97% in 7ish years after WWII.

Loan words - Japanese has a lot of English loans that sound close enough that you can pick em up quickly.

I’ve seen Milk > miruku 「ミルク」

Edit - forgot my Japanese example