It might say it's a renewal of your Windows Defender subscription, or some other subscription service. It might say the fee for renewal is $299 and it will be charged from your checking account. It will probably say something about 24 hours and create some urgency for you, a hallmark of scams. It will likely have a phone number that it says to call if you don't want the subscription.
DON'T CALL the number. Don't reply in any form.
This is a phishing scam, and these kinds are rampant right now.
If you've been scammed you are not alone. No one is immune from this kind of victimization, no matter how educated, how smart, or how wealthy you are.
Hearing about the details of these scams before you get the email increases your likelihood you'll recognize and avoid when it lands in your inbox. So tell your friends! Pass it on.