Medicine: Then you can either be a GP, or specialize in surgery, radiology, oncology, pediatrics, podiatry etc. Nursing: RN, or higher paid forms of nursing eg. Bachelor of science in nursing etc. Also, you can be a nurses assistant through a non-university education institution. Mental health: psychology, psychiatry (prescribing drugs such as antidepressants).
You could also do Dentistry or Orthodontics. (Dentists focus more on fillings, veneers and whitenings, orthodontists tend to specialize in braces and false teeth plates.
Some of these jobs are also an option to do in the military.
In addition to Estelle there is also a physician assistant or PA, medical assistant or MA, emergency medical technician or EMT, there are certifications for medical coding/billing, X-ray technicians, surgical techs, etc.