To change your Facebook login email, follow these steps:
Log in to your Facebook account.
Click on the down arrow icon at the top right corner of the screen.
Select "Settings & Privacy" and then click on "Settings."
On the left side of the screen, click on "Email Address."
Click on the "Add Email Address" button.
Enter the new email address that you want to use as your login email.
Facebook will send a confirmation email to the new email address. Open your email inbox and click on the confirmation link in the email from Facebook.
Once you confirm the new email address, return to the "Email Address" settings on Facebook.
Find the new email address you added and click on "Make Primary" button.
Enter your Facebook password to confirm the change.
Your new email address will now be set as your primary login email on Facebook. If you want to remove the old email address, click on "Remove" button next to it. Keep in mind that you will need access to your old email address to confirm the removal.