Thank your for sharing your question with the community, and thank you @seedy for your reply!
We have had a few similar questions on the platform before, it might help to read through the answers given on the threads:
Or this website: https://www.justlanded.com/english/Italy/Articles/Visas-Permits/Marriage-Divorce-in-Italy
But in general, these three links are interesting if you want to have a look at which steps you need to take in order to get married in Italy.
As for your question how the marriage affects your legal status - this link can help: https://www.justlanded.com/english/Germany/Germany-Guide/Visas-Permits/Family-friends
There is a German version that provides a more detailed answer, so maybe you can use a translation program for the paragraph about "residence rights after getting married" / 2. Aufenthalt nach Eheschließung https://www.justlanded.com/deutsch/Deutschland/Artikel/Visa-Papiere/Ehefragen
I hope that the information I shared here with you helps to understand the marriage process in Italy and the following rights within the German system a bit better. Please do reach out again if you need any further assistance!
All the best,