Depending on how much money you wanna make and the timeframe it is possible to make some money on freeroll.
First of all play freerolls just to learn the game a d other players way to act.
No need to use your own money until you know what it takes to do well in a tournament.
Then select your freerolls I play Bankrollmob and try to get into the three months leaderboard.
Open skill on pokerstars
is also very good learning to play against random opponents and try to do well in monthly leaderboard.
Then there is some ticket freeroll prize to win round two of the week with 2.000$ Price
But my favorit is the leaderboards.