There isn't a coating you can buy that will prevent paint damage from rocks and road debris. While clear coat will help protect the paint from very minor chips etc, your car will already have plenty of clear coat protection when you take delivery
I used to detail professionally, all of those 'paint protection packages' are nothing more than a good polish/wax job you can do in your garage for much less.
My product of choice is Zaino - I have used it on my GMC for quite a few years now and it looks great.