I'd have to say I agree with
Flippinstk. Hunting can be a very expensive, especially when first getting started.
I'm an avid hunter and a young female like yourself. Over the past 8 years I've spent plenty of money on guns, hunting leases, safety equip, and clothes. After a while, you'll get to the point where you'll only be spending money on the essentials like ammo, licenses, and things of that nature.
I wish it could be, but it's not quite as simple as finding a block of woods, parking your truck, and heading out for a monster deer.
Since your Granddad is a hunter, you may have the option of having him as a guide, using some of his gear, guns and ammo, and hunting whichever property he uses as a guest of his. This will be a good way for you to be introduced into the sport and it's always great to have a mentor.
I've fallen in love with hunting and all of the great experiences I've had while in the woods or in a duck blind. There is nothing like it in world. Good Luck!