Great to hear that you want to become a Pediatrician. The journey is a long and expensive one but, it is achievable. My son is currently a 1st year Resident Pediatrician. Here are some key steps to consider:
1) Make high scores on the SAT & ACT exams while in High School
2) Select a college or university that offers at least "Biological Science" (you DO NOT have to major in Pre-Med, Math, etc.)
3) Score well on the MCAT (Medical College Admission Test) the "first time". Retake it if necessary
4) Apply to "all" the Medical Schools of interest
5) Medical School = 4 years
5 a) Find an Internship (paid or volunteer) over a summer
5 b) DO NOT limit yourself to where you would like to get residency Matched
6) Residency = 3 to 4 years (this comes after Medical School)
6 a) Fellowship = 3 to 4 years (this is where you Specialize in, which is after Residency).
Good Luck to You!