First to say: though Munich is the capital of Bavaria, it's the most un-bavarian city in Bavaria. So to see typical Bavaria, you have to get out of the city, for example to the lakesites south of Munich. Starnberger See and Ammersee are only 30 (50) minutes away taking the Munich S-Bahn. I recommend either of these. Tegernsee is nice, too, the train ride is a bit longer, though. But it's right at the Alps.
In Munich, go to the Englischer Garten. Weather is still nice and it's an authentic Munich place. https://en.wikipedia.org/wiki/Englischer_Garten Don't miss the surfers at the Eisbach! The city centre is always crowded, no chance to keep away from tourists there. Lots of interesting architecture https://en.wikipedia.org/wiki/Architecture_of_Munich. I don't think your 14-month makes it possible to go to a "quiet" museum which Munich has lots and lots of, but maybe you can go to the Deutsches Museum https://en.wikipedia.org/wiki/Deutsches_Museum. It's tight to Munich quite deep as the founder, Oskar von Miller, was one of Munich's, Bavaria's, Germany's most influencial engineers and entrepneurs on the edge of 20th century.
If you are in need a typical bavarian snack, buy a Leberkässemmel or Fleischpflanzerl at the butchery at the corner. Any traditional Wirtshaus will serve you Schweinsbraten mit Kraut und Knödel or Haxe, and lots of Weizen. And sure, the waitresses have a Dirndl on there, too. So, really no need to go to the Oktoberfest.