I just installed Tomes on Xbox. It says it has installed but I'm just wondering do I have to do anything else to activate it? On the description it says that most of the books are in chests but I haven't come across any yet.

They pop up as random loot. According to the UESPWiki they have a 1 in 4 chance of taking the place of scrolls, so your best bet is to raid necromancer and conjurer lairs.

It also adds *very minor spoiler below*

I read about the Conjurer who attacks me but I read the description wrong. I thought it said one in four change in getting a book. Not taking place of a scroll.