You have a wide range of careers listed there with very different education requirements. If you want to be a veterinarian there are clear pathways - you find out what the requirements for vet school are and then plan coursework and internship and work experiences that will prepare you for those requirements. It would probably be helpful to find a vet (or vets) to informationally interview about their experiences and ask for their specific advice - this is true of anything that you might want to do.
For zoo design, landscape architecture seems to be the way that most people do it. It is a highly specialized field that you really have to pursue to find out where the openings are. Contacting some zoo designers and asking to informationally interview them and to ask for advice would be a starting place. They can give you advice on specific degree programs and possible internship experiences that would be helpful.
For working in a zoo in general there is no substitute for experience. If you have a local zoo where you can volunteer in their education program or as a keeper assistant or whatever is available for you age and experience level, that will show you what working in a zoo is really like. Most people work their way into the zoo world by building a personal network, and volunteering is where many people start. Zoo pay is usually not great, so that is something to consider as you look around for whether it is the profession for you.
Being a wildlife biologist probably will require some kind of biology degree. You would probably work either in academia as a research professor or for a government wildlife agency. If you can take a biology course at a community college and/or informationally interview some professors that would give you a sense of what their lives are like. They teach, they do research, they mentor students - it usually is not very glamorous, but it can be very rewarding if you have some specialized research interest that you want to pursue and/or you like teaching.
General advice: find people doing what you think might interest you for a career and reach out to ask for advice. Some people might be jerks and not respond or be helpful. Ignore them. There are many more people who would welcome your interest and try and answer your questions. The more exploration and networking that you do on the front end, the more equipped you will be to make some career decisions.