When it gets warmer and you are here in the warmer months, I HIGHLY suggest rooftop bars. Including Epic, The Wit, or if you go to Old Town, there's an entire street of great night life, with Italian Restaurants, and sushi. You just walk down and pick a place.

Beer gardens everywhere!

I love roof tops, festivals all that during the warmer days. But when it’s cold out I tend to go to cabarets with live music, cocktails, and tasty food . Another fun thing to do is visit some comedy spots while enjoying drinks and laughter. Hope you enjoy yourself, beautiful!

Not sure if this for you solo, dates or with friends.  
Lunch dates at Chicago Athletic Association and you can scoot across the street to the Art Institute or Columbia College has the Museum of Contemporary Photography that is nice walk through.  The roof top views at the Athletic Club view Millennium Park, the Lake and as far south to the Shedd.  The Chicago Cultural Center is also near and generally has a list of exhibits and events.  In the summer Pritzker Pavillion has everything from lunch time orchestras and in the evening concerts, movie series, dance there is pretty much something every night.  I always love High Tea and the Russian Tea Room in the loop is a nice spot.
For evenings the Museum Of Contemporary Art host first Friday music, cocktails, small bites. The Shedd has Jazzin at the Shedd basically another cocktail event at a museum but it’s on the lake and more laid back with Jazz over a DJ.   City Winery is a favorite of mine for wine and music. They also have a river walk location in the summer that I’d recommend checking out.   Aviary is my favorite cocktail bar if you are with a date or friends check out their tasting menu.  We did kitchen side chef table if you enjoy that Top Chef kind of thing it’s definitely a treat but it’s all cocktails and really small bites.
A no fail Symphony Center has events every night and tickets are always available. I love the Harris Dance theatre bodies, movement, costumes, precision.

A few OTBP Koval Distillery tour and tasting. It’s up in Ravenswood but probably $10/15 uber if your staying in the loop.  

So much great theater but check the off Broadway like Lookingglass, Stepenwolf or Comedy besides Second City like Stage 773.
I mostly hang out at music venues or grab a nice dinner.

The loop can get a little boring if you are going to be traveling in regular I’d suggest finding a new neighborhood to explore each time you are in. Nothing is difficult to get to either by train or uber .  You’ll find much better food, drink, activity, boutiques, artist. Although west loop has excellent dining options.

Ah that’s a lot of pretty specific info you enjoy yourself!