png transparency

yes, I tried.
if I export with the "transparent" checkbox all the white or empty parts become transparent, while I want only the empty areas to be transparent

I tried to put a white circle under the colored graphics, leaving the area outside the white circle transparent and free from graphics.
I also tried to give a flat white instead of the standard white.
I would like to avoid creating a non-white white (example 254, 254, 254)

I tried to export to PNG8 from illustrator obtaining transparency in the entire area where there was originally white