In my D’s case, she works with the pre-health advisers on her campus. She had a summer internship at a health clinic (edit: in our home city) after freshman year and now, as a sophomore, shadows a local doctor weekly during the school year (primarily shadowing out-patient surgeries). She attends a rural LAC so the pre-health resources have been invaluable to finding these opportunities. She did need to take the initiative to meet with them and continue to check in… a good lesson in persistence paying off.
In high school, she did some volunteering and shadowing found through personal connections, but this was limited due to covid.