Are you dimming a light attached as a load on the switch itself? Or are you remotely controlling a smart light?
For loads attached to the switch, the hold and release of the up and down are how you dim and brighten the attached load (as Bry points out). You have control over:
Ramp rate off to on and on to off when single tapping up and down
Dimming speed up and down when holding and releasing the up and down
Minimum and Maximum level brightness.
Default level when turned on
For all of these there are separate parameters when controlling the switch locally and remotely.
Color and intensity of the LED strip when on and off.
Color and intensity of each individual LED of the 7 LEDs.