Yes
If it is not choked to tight, yes.
Needs to be examined by a gunsmith.
Yes. It sure can.
Pellets or slugs. shotguns usually shoot shot or pellets, but you can shoot slugs. in Indiana we use a shotgun to hunt deer and use shotgun slugs, better to use a barrel with no choke in it. cylinder bore preferred.
of course you can
yes for a shotgun you need a rifle barrel DO NOT shoot slugs if you have a poly-choke!
Yes- but accuracy with slugs in any double barreled shotgun is not the best- the lines of the barrels converge. Imagine a very large X. Right barrel will shoot somewhat to the left, left barrel to the right.
Yes. You will have to shoot different brands and weights to see which one(s) your shotgun prefers.
Yes, but an easier method would be to sprinkle salt onto the slugs.
Depends on how old the shotgun is.
yes you can but onaly riffled slugs