Get yourself a 12 volt test light and check for power/voltage at the front window motors.
Basically,touch the test light to one wire terminal at the motor wiring connector and push the switch up and then down,it it lights up in either position,then touch the other termninal and do the same thing.,If it lights up,then you have a faulty motor.
If no power is going to the motor,i would suspect a faulty master switch.
Check the drivers door motor first.
Wiring coming thru the conduit to the drivers door can break and cause inoperative windows but it usually would affect all 4 windows.
All the windows get feed off the master switch as you know and get their ground thru this switch as well.
You can check the wiring in the pass thru conduit for an open...look at the color wires at the switch and check the wiring of that color coming thru..
Usually big gauge wires -10 or 12 gauge wires
What you can do to is take a jumper wire,use a 10 gauge wire and connect it to the battery positive ,careful not to touch the other end to any metal ....and then touch the other end to one of the terminals at the motor itself and see if the motor operates,may need to touch one then the other to see which one will move the motor depending if its up or down.If it moves,then you know the motor is ok.Do this with the connector disconnected from the motor...