So far only Airdrop or Bounty has given free coins to cryptocurrency enthusiasts, it's just that now there are a lot of scam projects, so you have to be careful,
especially airdrops, avoid airdrops that require you to send a certain amount of BTC to withdraw your prize, most likely airdrops like this are scams.
The OP seems new so he should definitely take this advice. If there's an airdrop requiring you to send any amount of BTC, that's definitely a scam and BS. If it also requiring you your private address, don't give it.