Just like a regular MD they have to attend college taking prerequisites before they can apply for the medical side of the schooling followed by residency requirements. Below text was copied from the website for the association of podiatric medicine. Maybe yours wasn't a typical Podiatrist. By todays standards however they will have had at least 7 years of school plus residency.
To enter a podiatric medical school, one must first complete a minimum of three years or 90 semester hours of college credit at an accredited institution. Over 97% of the students who enter podiatric medical school have a bachelor’s degree. Many have also completed some graduate study.
https://aacpm.org/becoming-a-podiatr...an/admissions/