If number of electrons in O2 molecule is 16 and electronic configration is 2,8,6. Then how it is stable?

• Oxygen atom has atomic number 8 and has electronic configuration 2, 6.
• Oxygen atom requires two electrons to complete its octet state.
• So two oxygen atoms  mutually agree and each oxygen atom contributes two electrons and so they have two shared pairs of electrons between them.
• Both atoms attain an octet, resulting in the formation of a double covalent bond between them.