Daniel, shotguns with smooth bore barrels are a different break in than a rifle. With a shotgun, you want to get a 25rd box of light low brass bird load, 25rd box high brass bird load and a box of full power buckshot or slug load. Fire 5rds of full power, 5rds of high brass bird and 5rds of low brass bird. Rotate in this order for 3 sets which is 15rds of each. This will give you an idea of the power range of loads your shotgun will reliably handle. Any burrs or shavings should now be smoothed out. Clean and lube then verify function with the last set of 10rds, note performance of each power level and stock up on what shot shells you intend to use for defense. Cheers and stay safe!

Clean and lube the firearm 1st, then get a couple inexpensive boxes of range ammo, a couple boxes of deffensive ammo, some milk jugs. And a bunch of sofa cans and 2 liters and let it rip.