How can i become a zoologist who works with turtles/tortoises?

You would study zoology but specialize in herpetology. Yes, zoology would be the way to go for now. You might also look into doing some hands on volunteer work with turtles or tortoises in your area. Keep in mind...many zoos will hire you and place you where you are most needed, not necessarily where you want to be. Unless you only apply specifically for tortoise/turtle keeper, but a job this specific might not even exist in most zoos. Working in a zoo may not require a degree depending on the zoo you work for..but they will want lots of experience in place of a degree. If you want to go for working with reptiles in the wild..you would want to get a Bachelor degree in zoology or herpetology if you can find a university offering it. (most have more general majors) and go on to get a Masters in herpetology (doing your thesis on turtles or tortoises)