This game is a retro style arcade shooter. You fight through levels of enemies that constantly approach and shoot at you, which is a basic enough construct, but the movement isn't generous enough to help you avoid the constant barrage of enemies, bullets and hazards. Additionally there is a progressive unlock system that provides you with various weapons and upgrades as you play and pick up police badges, but the progression can be a bit of a struggle before grinding for the unlocks.
I found myself just senselessly shooting offscreen to cut off any enemies with automatic firing weapons. Any type of uzi or machine gun usually meant guaranteed damage, so to counter this I ended up just spamming the shoot button, regardless of who might be in front of me. Of course this isn't the best approach, as there are civilians flailing around in the midst of things that would give you penalties if you managed to hit or kill them amongst all the chaos.
Additionally I found some control issues, namely I couldn't figure out how to play on controller without it being recognized as a second player. I can't rule out user error, but I managed to play the into/shooting range on controller, and from then on every time I used the controller I just had to play as player 2 and let my absent player 1 die.
Overall you can find some fun here if you repeatedly play the levels over and over enough to unlock more powerful weapons to aid you in your attempts to spam-shoot offscreen in order to stay alive. My experience may have been tainted a bit by the presence of "player 2", so your mileage may vary if you play a proper solo run.