Hello @rafael - welcome to our community! I closed the other thread that you opened because it contained the same question as this one. We try to keep discussions on this platform as transparent and easy to follow as possible. That's why it's better to keep all the information in one place ;)
You are right: marrying a German citizen grants you the right to stay for 3 years with a so called "Aufenthaltserlaubnis" (residence permit). After 3 years you have the right to get a "Niederlassungserlaubnis" (settlement permit).