Cash is a different beast (more dissimilar than it would first appear to be). Pick tourney or cash, wherever your heart is, and for the time being make that your sole focus. Books and online videos / articles will help, yes. Basically in cash because the blinds are fixed you have all the time in the world to pick your spots. Some of the nittier players will basically never get it in pre with anything other than AA (or maybe KK) because of this. Pot odds
and implied odds become king. Exploiting the tendencies of your opponents and pushing even small edges are key also. You can always just rebuy, right .
Your roll atm is pretty fragile for 2NL given your lack of experience with cash play, and the odds of you losing the rest are tangible I'm sure. Oh well. gl to ya.