In short, you can:
Enter Portugal without a special visa
Live and work in Portugal
Bring your family with you
Apply for permanent residency and/or Portuguese citizenship after five years
Access the Portuguese healthcare and education system (on the same basis as Portuguese citizens)
Travel freely in the entire Schengen Area:
Map over the Schengen area where Portuguese Golden Visa holders may travel visa-free
The Schengen countries include Austria, Belgium, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Italy, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, and Switzerland.
The EU members Bulgaria, Croatia, Cyprus, and Romania, are all required to join the Schengen area in the future, but as a Portuguese resident, you can already travel there visa-free.