Posted: Wed Feb 24, 2021 1:26pm
As I understand it post Brexit and the end of the Transition Period you will need a Visa from the Spanish Consulate first, and then you will need to apply for Residencia within a month of arrival on the Visa. That is if you are a UK citizen. If you have a European passport then you don’t need Visa and probably not Residencia or other third country citizen requirements.
You should speak to the Spanish Consulate where you are, about applications for a Visa - each person requires a Visa. Also medical insurance and to meet the new income requirements for the Visa.
Not sure what paperwork you have for Portugal and if you have any whether this can be used for what you need in Spain but no doubt the Spanish Consulate will confirm for you. Suggest in any event that you will need all your paperwork for the Visa and it could take awhile to get the Visa even if you qualify - but you will need it before you can make a Residencia Application!