“What is the best non-surgical hair loss treatment?”

That depends on what you want to do. Also if you are a man or woman and what your age is and if you want children (woman). Oral tablets - dutasteride and finasteride are probably the best topical - finasteride minoxidil also works well, PRP/PRF/etc. can be effective but is understudied. Red light treatment, supplements, saw palmetto, etc, etc - are understudied and likely of minimal to no benefit. Hope that helps.

The exact type of hair loss needs to be determined before any "best treatment" can be discussed. Visit a Dermatologist so they can determine (diagnose) the cause of your hair loss, and then discuss your treatment options. A detailed medical history, physical exam, and many times a scalp biopsy are necessary to determine the cause of an individual's hair loss.