I am a 3rd year university student with the hopes of becoming a veterinarian.
Now just to let you know the process of becoming a vet, no matter what type, varies from country, state, or province.
I'm in Ontario Canada, currently in 3rd year Biological Science at the University of Guelph and this is my process for becoming a vet.
Since you guys are in High School I recommend you taking taking grade 11 and 12 Biology, Chemistry, Physics, Functions and Calculus. These are usually requirements for a science program at any university. For my university the minimum average you could have for admission was 82%. This varies though, some schools will be a high 70 or high 80's.
For me, once you are in University you need to complete a minimum of 4 semesters(2 years), then if you have met all the prerequisites you can apply to the OVC (Ontario Veterinary College) during your 5th semester. You would then find out if you were accepted during your 6th semester. This sounds pretty confusing but pretty much you do 3 years of regular university, then if you are accepted into vet school, instead of doing your final year of university, you then start your first year veterinary college. Vet school is 4 years long.
For acceptance to vet school you need a minimum average of 75% in your prerequisite courses which are:
-Genetics
-Cell Biology
-Biochemistry
-Statistics
-3 different bio courses with a focus on Animal Biology
-2 humanities or social science courses
You also need volunteer experience. You need 2 letters of recommendation from different licensed vets. You should be trying to volunteer with as many different kinds of animals, especially farm animals. Try asking vet clinics or SPCA's.
You also need to write the MCAT and do a series of interviews before you find out if you're accepted.
Vet school is 4 years long and is general in all animal care. You will work with large animals (Horses, cows, sheep, pigs, ect.) and small animals (Dogs and Cats). You may not have any formal training with rodents or reptiles. This is why exotic vets are always recommended for Guinea pigs as small animal vets generally do not know much about them.
In your 3rd and 4th year of vet school you will get to work clinic rotations and get hands on vet experience. Then in your final year you get to perform your own surgery. It will always be a spay or neuter.
Once you graduate vet school you still need to work under a vet for 1 year. At that time you are eligible to write your exams to become a fully licensed and certified vet.
If after all of this you want to specialize in exotics or anything else (neurology, cardiology, ect.) you need to work under a certified specialist for 3 years. After that time there are more tests and things for you to do to become a licensed specialist in whatever field!
So this has turned into an unorganized essay but essentially, in Canada in order to become a full exotic vet it will take you at least 11 years to be able to work on your own.
I have decided to finish my degree before going to vet school though so I will still be a little bit longer.
If you have any questions don't hesitate to ask, it's probably best for you to contact your high school guidance counselor for info about university and beyond in your state!