EU certificate link.

Do you mean the EU Covid certificate? If so you can't unless you're an EU citizen or live there.

What you need to get is the Spanish QR code. On the Spain Travel health site: https://www.spth.gob.es/home , click on the button that says "If you do not have an EU Digital COVID Certificate, click here to access."

You can fill out some information ahead of time, but if I remember correctly, you cannot complete it until you are within 48 hours of flying.
Once you complete it, they will tell you it has to be approved, but that comes pretty quickly, along with the QR code.

We traveled to Spain on April 21, and home on May 21, and no one asked to see the QR code, but you are registered in the system anyway.

Hope that helps.

Thank you! Do you know anything about Portugal or London? We have a day or 2 there also.

You don't need anything for London. All Covid restrictions have been lifted. It's like Pre-covid days.

Right now, to enter Portugal you need to have a negative antigen test within 24 hours of arrival.

Is that true or is vaccine sufficient for Portugal

Officially yes you need a test for Portugal. However they say they only check about 20% of passengers and I believe that is airports. Depending on how you go from Spain to Portugal they may not ask.

Thank you!