The kind of resident permits that suits you and your husband best will depend on your specific situation and purpose, as there are many kinds of temporary resident permits in Portugal that you can apply for. Any of these, however, only allows you to live and work in Portugal. Nevertheless, any of the mentioned resident permits will grant you free access to the Schengen Area, which allows you to freely move and do business in other European countries. The application must be done until Dec. 31, 2020, as this is the final date of the transition period agreed between the U.K. and the European Union. You can find more information on this matter and on Portuguese resident permits on this website: https://imigrante.sef.pt/en/brexit/
How can I apply for a Portuguese resident certificate and work in other EU countries?
I’m a British national. If I apply for a Portuguese resident certificate, then am I allowed to work in other EU states with this resident certificate? I mean after Brexit.
The residence permit in Portugal will only entitle you to live in Portugal. However, once you have acquired that residence permit, you will have the rights of any European citizen, which means you will have the right to free movement of persons and goods and to do business in other European Union countries.