I've built my whole bankroll from freerolls, got up to about $650. So, it is possible. Here's some tips:
First, build your bankroll up
a little bit before you try to play real money
games. At least to about $5 or $10.
Second, now, this will seem weird and you probably won't want to do it, but before you play real money games take a little 5-7 day break
. Why? Freerolls and real money are a lot different. If you just jump in you'll do a lot of the same things you do in freerolls and you'll get crushed. Even if you're a good player when you do things enough they become habits and you want to get out of your freeroll habits.
Third, follow good bankroll management
. At first, it will be impossible, but once you can, you need to follow it. It's easier said, then done, because you feel likes it's free money, but if you don't follow bankroll management then you'll be back to playing freerolls.
Hope that these help.