If you want to find a real Airdrop, you should go to the Real social media account of that Airdrop and check its announce whether they have started such an Airdrop. Check the details of the project and contact the admin through telegram to get information about it. By the way, some Airdrop have given a lot of profit. Hydro, energy, uniswap, TWT, SFP etc ...
This is the best way to determine if your in-join airdrop is legit. This is exactly what I do when I see or want to join an airdrop before, but I still look around from time to time but only a select few. You need to conduct your research and not just rely on what you have read and shared by others. You need to look at the official socmed accounts and sources so that time and effort are not wasted if the only thing you can join is useless and fake.