More than likely it’s an over the range microwave with an integrated vent which will either recirculate the air or is vented outdoors.

Pull and sell the gas stove in favor of an induction range like Frigidaire or Bosch.

What’s wrong with a gas stove?

"I want to know is this gonna be a probably later on and where is the vent?"

Is the microwave mounted below a cabinet? Look inside that cabinet; you may see the duct for the microwave oven. However the microwave could be ducted out the rear in which case you wouldn't see the duct. If the oven is configured to recirculate the air, you'll feel air blowing upward from the top-front of the microwave when it's on.

Typically, the distance between the cooktop and the cabinet supporting the oven must be at least 30".

Induction has many benefits. One is in use you have much less created waste heat making the kitchen hot in summer. You'll need less exhaust power because of that. Another is the super easy cleanup. Just a paper towel and a spray of cleaner and you're done. Induction heats faster and you can change a heat setting faster.