Do not plug 120 VAC appliances into 240 VAC.

However, where there is 240 VAC, 120 VAC is available. The way utilities develop 240 VAC is to connect across Phase A 120VAC and Phase B 120VAC which are out of phase with each other to develop 240 volts single phase.
Connect from the white common wire to either phase a (red) or phase b (black) to have 120 VAC single phase.