From MUC you can fly to Venice, Verona, Bologna, Milan, Florence, and of course Rome. You can also take the train from Munich to those locations (a bit longer journey).
If you have never traveled to Italy, Venice, Florence, and Rome are the most visited by tourists. Verona is also visited by many. Milan has the second most visitors after Rome, but most are business travelers.
However you don’t have time to visit all in just seven days. You need at least 2 days for Venice and 2 for Florence. One full day for Verona. And at least 3 in Rome.
If you take the train Verona, Bologna, Florence, Rome are along the rail itinerary coming from Munich to Rome. Venice is a bit of a detour to the east.
For flights from Munich look into Lufthansa or their partner Air Dolomiti (which operates most of Lufthansa flights from Munich to Italy).