It is a well-known scientific fact that:
Carbon dioxide, CO2, is a linear, symmetrical and nonpolar molecule. The bonds between carbon and oxygen are double bonds.

Oxygen is more electronegative than carbon. So, each carbon-oxygen double (C=O) is polar covalent with a partial negative charge on the oxygen atom.

Carbon dioxide has two polar covalent bonds and yet it is a nonpolar molecule

Let's add up all the bond dipole moments in carbon dioxide.

There is no net dipole moment. CO2 is a nonpolar molecule.