There are several things you should do before even trying to start the bike.
Yes, you'll want to get a new battery, an AGM like vulken mentioned above, a long with changing the oil and filter. I'd use a hairdryer to heat up the crankcase before draining.
You'll want to check the air filters....1. To make sure they haven't disintegrated and you end up sucking foam into the engine, and 2. To make sure there aren't any mouse or wasp homes built in there. (For some reason mice and wasps like camping out there)
If it truly sat for 11 years you'll likely have issues with goo in the carburetors. I'd pour some Sea Foam down the fuel lines and let it sit for a day.. you may end up having to pull the carbs and cleaning them, but I'd try this to start with.
Yes, fresh fuel ... Dispose of any fuel in the tank and check for rust in there.
Although this isn't needed to just start the bike, I'd be concerned over the condition of the tires. If the rubber on the turn signals rotted out, good chance the tires should be replaced too before trying to ride it.
Not sure how much experience you have working on motorcycles, but you should pick up a service manual for the bike. Big help if you need to do more.
I'd spray a little oil into the cylinders before trying to start it for the first time. (Just remove a spark plug from each jug and replace after shooting some oil in the hole)
After you get to that point let us know what happens....