To measure resistance, apply a current and measure the voltage. The higher the voltage, the higher the resistance. To measure conductance, apply a voltage and measure the current. The higher the current, the higher the conductance.
A capacitor does not have conductance, it has susceptance and susceptance is not the same as capacitance. Susceptance is the inverse of reactance. Susceptance and reactance are the same thing stated in a different way. For example, if you were in a valley looking at a mountain peak, you would say that is high but if you were on the mountain looking at the valley, you would say that is low. It is the same distance but stated in a different way.
An inductor does not have conductance, it has susceptance and reactance. Inductive reactance is considered positive while capacitive reactance is negative, so when you connect them in series the resultant reactance is the difference.
Impedance is just a term for reactance and resistance where the phase angle is not 0 or 90 degrees.
The inverse of impedance is admittance. Resistance and conductance apply in DC circuits, impedance and admittance apply in AC circuits.