Chemistry, physics or biology for nursing?

Besides the nursing program in any UC or CSU’s which science is best to major in if I wanted to be an RN? I know nursing is really impacted so I need a alternative major that could eventually lead to nursing.

And which one is best if I wanted to be an orthodontist? Im stuck between two careers, is there a major that could lead to both?

I suggest you look into Dental Hygienist school if you want to be an orthodontist. They have prereqs of bio and chem and I think Anatomy and physiology.

Are you in college or high school now? You should talk to a career counseling advisor or guidance counselor to understand what it would take to get into dental school and to eventually become an orthodonist. It is much more difficult and longer process than to become a RN. I understand that applicants to dental school are expected to work in a dental office for a while in order to be considered.

I imagine the prerequisites to get into dental school are similar to med school - including lots of biology, anatomy and chemistry. You should read up on the admission requirements for various dental schools in your state. There are probably discussions about it on this website, too.

I am under the impression that many dentists earn much less than medical doctors.

You may find that being a RN is a more realistic goal.

If you cannot get into a RN program, then you should try to complete as many classes in a BSN curriculum as you can in your present college. That will make it easier and quicker to transfer into a BSN program at a different college in a program for students who already have a non-nursing bachelors degree. However, those types of programs typically do not offer much financial aid. That is another reason to try to complete as much of the curriculum in your current college, because the second degree will probably charge you per credit hour.