the answer is a big YES it will be good for you cause it will help you get fit and healthy, when I started cycling I weighted 260 and now I'm 209 so just get you a good bike and ride hard dude, ride and ride like there is no tomorrow.
The GMC Denali is not a very highly-regarded bike. Looking at the specs, it has low grade components, including a Shimano group that I've never heard of. And at 29 pounds, it's heavier than my 1985 steel Schwinn Super LeTour. You can do much, much better for not a lot more money.
Look at undervalued brands like Diamondback, Fuji, and even some of the Bikes Direct house brands like Dawes or Windsor. Google Bikes Direct for the link.