There's a D&D-like game that I used to play that actually has education requirements to read different languages. If your background didn't give you the trait, you had to learn from someone who knew how to read.
It made for some interesting role-playing when normally intelligent people were playing illiterate characters.
rambling about said game
There were "basic" and "high" forms of the standard language, but there was a language for most species as well as "lower" speeches that non-sentient beings could use to communicate. Each language except lower one's had their own written language and associated trait to understand.
So if you put all your stats into STR, then you'll be lucky to read your own language before dying of old age, as your INT modified how easy it was to learn.
Learning just entailed being with someone who has the trait and is willing to teach you, you roll and add your modifiers and after a non-specific (up to DM) amount of time, you can put some stat points to learn the trait.

I can help you out with 2 of those 3 things!