Can blackheads falls off on their own?

Not often: Wash face w gentle cleanser 2x/day & use oil free products. No oily hair or heavy foundations. Exfoliate occasionally. Try not to pop pimples. Avoid touching face (cradling chin in hands). Remove makeup before bed. Shower after strenuous exercise. Consider otc products (salicylic acid or benzoyl peroxide). If > mild acne see dermatology (discuss meds, comedone extractor, pore strips, etc.).

I squeeze mine: They are blocked oil glands with a plug which can be squeezed out. Salicylic acid and tretinoin (retinoic acid) are very effective. See a dermatologist if they are large or numerous. They are not dirt. Of course they may often come out without any treatment.