I want a Dog but I have a cat?

I want a puppy German Shepherd so it can grow into loving me, but i have a 1 year old cat (female) I don't want them to hate each other, and my cat is really territorial, she like senses me when im by her food or litter box, i mean she looves me, and i ant a German shepherd so much, they're so smart, and cute, and loving <3 What can i do? will they hate each other...? and i want to get a male German shepherd