There are a couple common causes of creaks and pops.

Many newer bikes have press-fit bottom bracket bearings that are prone to creaking. I have no experience with these so can offer no advice. If you have a threaded bottom bracket make sure it is good and snug in the frame. You would have to remove the cranks to do this. As you pull the cranks off, listen closely as the interface between crank and bottom bracket spindle can also be a source of noise, usually noise that occurs regularly with crank revolutions.

The seatpost interface witht he frame and the saddle interface with the seatpost are often culprits, but if you cleaned and retightened then it's likely not that.

The most insidious cause, often making a very loud and annoying noise that is extremely difficult to diagnose (but dead simple to fix) is the cable housing ends in the cable stops on the frame. IF there is corrosion or debris in the cable stop it will make a creak noise with any slight movements of the handlebars, and this noise echoes through the frame. To fix this, first try pulling the cable housings out and wiping down the ends of the cable housings and the inside of the cable stops. The noise migh also be from inside the cable ferrules (cable housing ends caps) if the ends of the housing are not cleanly cut.