Et al., the abbreviation of et alia (or et alii or et aliæ, depending on the gender), means and others; etc., the abbreviation of et cetera (sometimes spelled etcetera), means and so on. Thus reserve et al. to reference people and etc. to reference things: Of all the heavyweight greats—Ali, Foreman, Frazier, et al.—Usyk is my favorite to watch and All flours, be they white, wheat, rye, etc., make for excellent bread.
Neither et al. nor etc. should ever follow the conjunction and—et is the Latin word for and.