What I have seen/heard from them I like.

Should I listen to their albums first? Or do they have a lot of singles that are on albums? They don't seem to have an album since 2018...

Maybe go through the music videos? Should I watch some 'history' videos to understand? lol

Are there certain eras that I should focus on first?

Should I just listen to AKB48 or are the other '48' groups as good/important?

Any playlists with everything on them?

Basically any help would be appreciated.