It's your responsibility to send the schools your letters, here is what letter sending services are allowed, if you are in school then your school may offer them for free:
Have one more question about LoRs. So for my podiatrist, is there a specific form he has to write about the LoR for me or does he write it how he wants? And also how do the schools know he is writing it for me? Does he put my name and school or any other credentials on the letter?