There are two types of Digital Nomad visa:
A short-stay visa allows you to stay in Portugal for up to 12 months. It cannot be extended and it is used to obtain a residence permit. But if you are planning to stay in Portugal for one year and then move on to explore other countries, then this option is for you.
A long-term visa is ground for obtaining a residence permit for two years. It allows you to stay in Portugal for more than a year. This is a convenient option if you want to live in Portugal and get a Portuguese citizenship afterwards.
Where can you get this visa?
You can apply for this visa only in the country you have a residence permit or citizenship of.