My advice would first be to try volunteering in a hospital to see hands-on if it would be something you might like. Make sure blood and guts doesn't gross you out too much before applying!
Once you know that's what you want, you can apply to nursing programs! You have two options with nursing school; you can either take 2 years of pre-requisites (anatomy, chemistry, biology, etc.) at a community college, and then transfer into a 2-year nursing program that includes nursing classes and clinical experiences.
The other option is to apply to a 4 year nursing program at a University! They will space out all your science and nursing classes and clinicals for you.
Once you finish your 4 years of nursing school and obtain your bachelors degree in nursing, you can work in any unit you want! There's labor & delivery, neonatal intensive care, pediatric, operating room, adult surgical intensive care, outpatient doctors offices, and many more options. Nursing school clinical rotations should have you work in most of these units, so you get to see what you like!
Once you've been a nurse for a couple years, you can apply to nurse practitioner school to get a masters or doctorate degree in the field that you work. Nurse practitioners can prescribe medications and diagnose patients, but it takes some nursing experience before you can go back to school for that. Also, if you take nurse practitioner classes part-time while you work at a hospital, they'll usually pay for some of your classes!
Nurses have to know an incredible amount of information, but its a rewarding field with a lot of flexibility to work in any field you want, and to further your education.