Freerolls are a little different from the others games, there are different levels of players depending on the freeroll that you wanna play.
I advise you to play with caution, but sometimes you will need to risk some spots.
Try this:
UTG, UTG+1: TT+, AT+, when you are deep you can add to your range, AXs, any pocket pair, trying to hit something on the flop or fold. In the case a AXs, you will try to flop a flush or flushdraw, maybe straight or 2 pair, but caution with what the others cards can give to other players range.
MP+1, MP+2, MP+3: 77+, A8+, QJ+, JT+, when you are deep you can add the same cards like in the UTG, maybe you can add suited conectors 87+, KXs, trying to hit on flop, but don't put so many money in the bet.
HJ, CO, BTN: You can play all the range that I have given until here, inclusive you can try to make Cbet, with the hand extra that I given to you try to use only until the flop, and you can try to steal
bluffing in position.
SB, BB: in these positions there are something to think before get into a hand, like the amount of players in the hand, if there bets, 3bets and 4bets, I advise you to play only the premium hands, if there so many actions before you, like KK+ and AK, if there is only few players calling the blind, you can play the same of the UTG only completing the bet, or if you are deep you can make a big bet trying to play against less players in the postflop, the ideal are play against only one.