Welcome from Savannah, Ga and congrats on your Green Mountain Grill purchase.
I would recommend the following:
First, run it for about an hour at 350 to burn of any manufacturing oils.
Second, is seasoning. Spray a light coating of Canola Oi and load of the rack with bacon. Run at 225 for awhile and than 300.
Third: do some cooking for instance a 10 lb. Boston Butt is about the most forgiving meat to smoke.
A couple to three hours at 170 for smoke. Up the temp to 225 until done which is about 205 degrees.
Takes about 1 1/2 hours per pound.
Next one foil at 160 internal until internal temperature of 205 and see which one you like best as both ways are good.
Or roast a chicken first and you will find many recipes here and on the internet.