I only knew 2 students who worked. One was a tax accountant before medical school and worked in April of our 1st and 2nd year preparing taxes. The other worked in valet parking and combined his workout with his job by running between cars while parking.
A job would interfere with your education and lower your grades.
If you can keep your expenses down (live with parents, attend community college which can be free in some cities, complete your degree at an inexpensive public institution etc) debt doesn't have to be out of control. However the typical student does not do everything they can to decrease expenses then has to be stressed during their first years of practice.
After medical school, the next step is residency. During my residency I was able to moonlight as a physician on my weekends off, but that was 20 years ago and I am not sure if that is still possible.