For beginners in careful participation in airdrop, easy way of knowing the airdrop scam:
3. Airdrop by requesting to enter privatekey
Almost anything that would seem suspicious to you (maybe your guts told you so), are probably scams. Airdrops usually asks for your email, username, and ETH address but if things turned out like this, asking for your private keys and such, then it's probably a SCAM and it's trying to phish your datas. If tou think you've been phished, immediately reset your private keys. You might save your account with this.