There are so many things to try on Yangon nightlife including clubbing , pub , local beer shop , good time at kandagyi palace, traditional culture shows, you just has to follow your taste.
Here is some information for you and hope this is helpful for you.
You can find about Yangon Events here
Myanmar Nightlife culture is pretty simple . Staying at home with family , watch movies together. You won't not believe even Myanmar teenagers love to do
Some teenagers love to hangout with friends at kanbaung on pyay road and kabaraye pagoda road to play gaiter, drinking together .
This street is where, in the evening, the road turns into a long line of BBQ restaurants. Ok, the restaurants are there in day-time too but then the street is still 'open' to cars. At around 5 the street gets taken over and the restaurants expand their business to outside
It is a nice place to sit and have some BBQ-ed fish, a beer, or whatever else you'd like. You choose a BBQ stand that has items you like and they'll serve your food to you.
One thing that you can't find but should ask for is Malahin (not sure if this is the correct way of writing it but that is how you pronounce it). It is a spice mix of vegetables, meat, and noodles (they can also make this vegetarian). My favorite dish in this street.