Just playing the game and talking to everyone of a specific race can really help out a lot with culture especially in their home areas. For example if you are in shadowfen and you talk to or listen to a bunch of Argonians you can really learn about many rituals. Dark elves are tough as the only thing they talk about is politics and they never explain the differences between regular necromancy and there risen ancestors. Also remember true nords dance on tables
Argonian Master Race
PAWS (Positively Against Wrip-off Stuff) - Say No to Crown Crates!
If you're looking for lore specific to ESO I'd recommend checking out The Emperor's Improved Guide to Tamriel. It's delivered in a story format, and gives a pretty good overview of the current politics and culture of each province.
Read the books in the game, don't just collect them. This includes the random bookshelves along with the white and blue lore books. Although, the Imperial Library should have most of them to read there.
If you have done the Mages Guild, you can read any book you have seen in the game on that character.
Enjoy the game, life is what you really want to be worried about.
PakKat "Everything was going well, until I died"
Gary Gravestink "I am glad you died, I needed the help"
Read the books in the game, don't just collect them. This includes the random bookshelves along with the white and blue lore books.
Would you recommend collecting all letters and documents, like from the eternal memory? Because I have read all the Lore Books from Morrowind, Oblivion, Skyrim and ESO, but I still don't quite get all of it.