When I go to a donation page for my account, it opens PayPal that puts my email address there for public. I want to hide my email address. That's my personal email address I use for my personal private purposes, I don't want it to be public. Can I instead use paypal.me link that I have generated or link my PayPal account to my DaFont account, which should verify me as a valid recipient as well, and may help me to hide my email address? Especially paypal.me link, which doesn't show my email address, and lets you to send me a donation. PayPal requires people to register anyway to pay, so whatever. My email address is covered. Maybe linking my Patreon page would also be nice, this gives people an option.

That's a PayPal policy and you can't do anything with that. As for using your paypal me link, I do not know if that is possible but I really doubt it.

What you can do is create another email account and add that email address to your PayPal account. Remember that you do not need to create a new PayPal account. When you are at PayPal click on the gear icon next to the logout link. You will see the email addresses linked to your PayPal account. Click on the +Add link and enter your new email address. If Paypal wants to validate that new email, wait for the validation email from PayPal. Follow the instructions on that email. If your done with that, login to Dafont and go to your My account page. Then click on the Donate link and enter your email address on the appropriate box. The next time someone clicks on your donate link, that person will only see your bew email address and not your registered email address here at dafont.

As for Patreon, you can add that to the User comment on your Dafont profile page since you already have entered a link, You might also consider adding your Patreon link to the Note of the author on each of your fonts.