Hi bjornseo and welcome to CC
In my opinion, to learn the foundations of the game you will do better with a buy-in of 100BB regardless of the stakes. Reading poker books
is good obviously but keep in mind that most books assume that players think and if you are playing micros, most don't. This means that sometimes you read something in a book, add it to your arsenal and it just goes wrong time and time again. This is especially true in the online micros.
Bet sizing is a great example: your bet size should be between 2/3 to 3/4 of the pot until you start to understand how a different size will change the pot geometry, odds
, fold equity, princing in, yada yada yada. I personally bet 80% of the pot.
Opening is another. Most people feel that a 3BB open is standard. In the micros I open with 4BB.
Start at the lowest stake with a bankroll of around 20 buy-ins and build from there. Assuming you'll be playing micros, bet for value, don't bluff.