Be sure the guidance counselor and your teachers know what your career goals are so that you can take the most advanced versions which will best prepare you for college.
Good luck and write back if you have more questions.
The admission requirements for most vet schools include specific hours and levels of science and other subject courses (usually called "pre-requisites"). If you can take AP level courses for college credit in high school, & the schools you apply to will accept these courses for completion of admission requirements, you will be ahead of the game in your college work when you graduate from high school. For the same reason, if you take community or junior college level courses, check to be sure they will transfer as acceptable credit for your pre-requisites.
Todd recommends the following next steps: