Heater blower stopped working in my 2000 ford expedition stopped working

Be certain to check your fuses, and also the ones that are under the hood.
Then, one of 3 likely events.
First, find a plug-in outside of the blower motor, and with key on and dash switch on, see if juice is getting to the blower motor.
If not, ether the relay or the blower is bad.
The most common problem is the relay, second most common in the motor, third is the dashboard switch.
God bless your efforts.