Yes, you can dim LED troffer lights. However, the troffer will need to have dimming features to dim. Not all LED troffer lights are dimmable so check to see if the LED troffer is labeled “dimmable.”
If the LED Troffer is not dimmable you can either purchase a dimmer switch to install with the troffer light or purchase a compatible remote to adjust the fixture’s brightness.
To find how many troffer lights you need, you will need to follow the calculation to see the correct amount.