Consider any email that you have used in a crypto-related site or project as public knowledge. Many of these projects lack the resources to keep your personal information secure, or just sell or share them, or in some cases, they are just scams.
I received this email a few hours ago, and it seems like it came from a decentralized search engine project called Presearch (do check them out, they are interesting). I have a Presearch account so I opened it:
The sender used <support@presearch.io> as the name of their email account and If you don't look closely, you may miss the fact that It's not their email address, as you can see in this picture:
Also, the link they sent, even though it looks like the official Presearch website, will direct you to Its second part (after the @ ) and if you go there and connect your wallet your funds are gone.
So just be vigilant and remember, any direct message or email you receive about an airdrop, is 99.99% fake.