While "easy" is a relative term, some academic programs to become a doctor have fewer requirements than others and can therefore be considered easier. Non-specialized doctors tend to have it easier than specialized doctors, like neurologists or cardiologists, with less education and shorter residency terms.
A general practice doctor has the least amount of requirements for any medical doctor. While these doctors do still have four years of medical school and one to two years of residency after completing four years of undergraduate education, this is the minimum amount of education any medical doctor must undergo.
A pediatrician is a general practice doctor for infants, children and adolescents, ages 0 to 17. Similar to a general practice doctor for adults, pediatricians go through eight years of education before beginning their residency, which lasts three years. After this, they are eligible to practice pediatrics.
While not a medical doctor, a podiatrist is technically a doctor and receives the designation DPM, or doctor of podiatry medicine. These doctors, which treat the feet, ankles and lower legs, must complete an undergraduate program and a four-year podiatric medicine program before beginning their one- to three-year residency.