is it ok to have a beer or two the day before upper eyelid surgery?

You should refrain from alcohol use prior to surgery as it increases your risk of bleeding and bruising. It is simply not worth risking it.

Excessive use of alcohol prior to surgery can prolong your bleeding time and lead to more swelling and bruising in the postoperative period.  Although having a beer or two isn't absolutely contraindicated, it is preferable that you abstain in order to give yourself the best chance at healing quickly.