I'm not 100% sure, but I would think that there is a choke in the gun. I'm not real sure what kind. If you want to add a choke, for example, briley, patternmaster, ect, I'm sure it would not be a problem. Best thing to do is to check out the owners manual, that would give you exacly what kind of chock you have.
That Maverick should have come with a choke. I purchased that gun for my son as his first shotgun. Go to JAXs in Ft Collins they have a good selection for Mossberg, Sportsman Warehouse will not carry Mossberg products.
"The incomparable valley with the unpronouncable name." Theodore Roosevelt, referring to the Uncompahgre Plateau,1901
I'd highly recommend that if you aren't sure whether you need a choke, ya might wanna hook up with some guys here who have some property, some dekes, and who can call, or yer gonna prolly need super -duper-xtra -mega full plus, cuz it doesn't sound like you're real experienced? No shame in that, but do it right - get out with some ethical hunters and learn the sport right from guys that have been doin' it fer a while. Not taht you'll find any guys like that on here...
Hunt geese, that gun should have a choke, it may not have a screw in choke maybe a straight barrel if you will look on the side of the barrel near the reciever it should say Full Mod or IC. if this is the case then you are stuck with what you have. I am pretty sure the 88's don't have screw in chokes
Sorry about the spelling...I'm about 10 beers into the evening.........Is it Oct yet