Hi Brida,
Congrats on having your first credit card... Make sure you use it wisely and don't make impulsive purchases. Its very easy to get carried away and spend money you dont have...
The 7.99 means that on purchase of good i.e grocery or a camera etc.. you will have to pay 7.99% interest rate.
14.99% is the interest rate that will be charged on any cash advances you get through ATM using this card...
Special thing to note is the default rate.. which in your case is 28.99% which is quite high... (Default rate applies when you miss one or two payments on any of your bills)
Hope that helps..
have a nice day