Since this is an elective procedure that does not involve halting disease progression, the easiest option is just to wait. However, no one wants to put their life on hold forever, so you could just ensure that precautions have been met.
Are you vaccinated against COVID? If you are, you already have a substantially reduced risk of contracting COVID. You could call the clinic and ask about the measures they are taking to reduce risk of COVID. Are the staff vaccinated? Will you be waiting in a room with other (potentially unmasked) patients, or taken to a private room immediately? Your choice to have the procedures now versus waiting may depend on your vaccination status and the clinic's response to questions about patient protection.
Skin tags don't hurt, they don't cause any symptoms at all, they just appear to some to be unsightly. For that reason I would personally wait. On the other hand, if it was anything you had to get done to perform properly or to reduce pain, I've found that health practitioners are being as careful and protective as they can. I've been to dentists, eye doc, and even had the wax cleaned out of my ears during the pandemic, but all of those were things I had to do in order to function -- can't hear with the wax, can't see or pass my driver's test coming up without new glasses, and I have teeth problems. In all cases, protection was as much as one could do without offering tests to everyone first and none of them did that. Waiting rooms are a thing of the past, they only schedule one patient or two and everything is by appointment, no drop-ins. Everyone must wear masks, though with the dentist there does come the point you have to take it off. It would also depend on your risk factors -- while 64 puts you in the age risk category, if you have no underlying conditions, which I didn't have, it's much safer than if you do have some of them. I did avoid all this for awhile, but the pandemic wasn't going anywhere and it still really isn't, not any time soon, especially not in the US. But again, a skin tag if that's indeed what it is has absolutely zero health consequences, and so for that I'd wait.