Can my 06 Tundra tow this?

You don't subtract the truck's weight from it's tow rating. If it's rated to tow 12,100 then the trailer can weigh up to 12,100. That will work fine if you're towing a boat or a flatbed trailer or something like that. RVs are probably the most difficult of all types of trailers to tow. They have a huge frontal area, huge side area, large percentage of tongue weight, and very limited ability to move things around to adjust the tongue weight. Most 7,000 pound RVs will have about 900 pounds of tongue weight. That will be the sticking point with your truck as it's configured. You may be able to upgrade your hitch to one that will handle more tongue weight.
Your truck's payload capacity (GVWR - truck's weight) will be your next limiting factor. When you start adding passengers, pets, truck accessories, WDH, and tongue weight you will run out of payload really fast.