You aren't the only person that is thinking about moving to Portugal. A lot of people have done it before you. Those people had the same questions as you. So why shouldn't you ask them what answers they found. Or maybe you can help other people find their answers. That's why there are a lot of online places to connect you to other people who can help you figure out what you should or shouldn't do. 

Group (Link)Description
British expatsForum for British people that have moved or are going to move to Portugal.
ExpatforumThis forum connects people from all over the world we have decided to move to Portugal or are still considering moving to Portugal
Expat ExchangeThis forum gives you advice, information and expat connections about a life in Portugal. The platform is also full of tips and experiences to make your moving experience easier.
Expat: Portugal forumThis forum answers your questions about living in Portugal. It also connects you with other expats who can give you advice.
Expat focusThis forum is for everyone who is moving or living in Portugal. It helps you with the practical questions you have about moving. But you can also find some properties that are for sale or rent.
British expat forum
This forum gives you the chance to ask other Brits in Portugal for advice on all matters regarding live in Portugal. Share your experiences and questions. Who knows maybe you can help other Brits too.
British in PortugalFacebook community that will keep you updated about Brexit negotiations and your rights as a British citizen in Portugal.
British expats in PortugalFacebook community for people who want to connect with other British expats living in Portugal.