To earn in airdrops the only thing you need to do is simply.filling the form and thats it wait until if you are qualified to receive their tokens but just a simple of advice becareful in airdops now a days some of airdrops are scam you need to choose a good airdrops before you joining them
I am not that selective when choosing airdrops, I just try to choose those that don't require KYC in order to maintain my personal information safe.