1) Would the polar bear lick over the guys body first before feeding?
He wouldn't spend a lot of time doing this because he'd be eager to eat, but would probably lick a bit to make sure he thought this woudl be good food.
2) Would it lick over the front of the guy wet and very tight red shorts?
He'd most likely give them one swipe of his tongue, then realize they were not flesh, and would want them gone.
3) could it lick up and down the length of what was hidden in the front of the shorts feeling it move as it did so?
Depending on how hungry he was, he might do this out of curiosity.
4)Polar bears area quite intellegenat icould it push its snout down near the right hand side of the swimsuit (lift side as you look at pic) and get its tongue and snout in to explore it?
He woudl be able to do that, but it's more likley he would rip off the shorts as soon as he realized they weren't edible. Then he coudl do all the exploring he wanted.
5) could the bear tear the red trunks off with its teeth, were would it grab it ?
As he tore open the abdomen, the bear would come to the waistband first, so probably would tear from that point.
6) once it had removes the red trunks coverd in blood from opening up the belly area if hungry enough would it eat the red trunks?
No. It might chew on them a bit to get the blood out, though. Kind of like chewing gum.
But the bear knows the shorts are not food.
7) as you said ,the bear is not used to what the guy has under the shorts.Would lick over the entire lenght and contents of the guys groin?
Yes, he might toy with it a little and then start eating.