Assertion $\left(A\right):$  The dipole moment helps to predict whether molecule is polar or non–polar.
Reason $\left(R\right):$ The dipole moment helps to predict the geometry of molecules.

A polar molecule has non-zero dipole moment and a nonpolar molecule has zero dipole moment.
Hence, The dipole moment helps to predict whether a molecule is polar or nonpolar.
Thus, assertion is true,
The dipole moment and the geometry of molecule are correlated. Different geometries will result in different values of dipole moment. Hence, from the value of the dipole moment, the geometry of the molecule can be predicted.
The dipole moment helps to predict the geometry of molecules. So, Reason is true.