How Avogadro concluded the number 6.022 . 10²³. How he came to know about this number.

Amadeo Avogadro was an Italian scientist who specialized in physics but experimented with chemistry once Avogadro was testing his hypothesis he was experimenting with gas molecules insisting that equal volumes at a fixed temperature and pressure have the same number of molecules his findings would later become Avogadro's Law and thus mole was bobo