What does it mean to show off nd on Sony camera screen?

Professional camera screen displays ND OFF, indicating that the filter is off. In this case, it may affect the exposure, but it can still be filmed.

There is a third key on the left side of the fuselage, ND 1 ND2 ND off.

If you put the machine in the automatic position to shoot, it will automatically judge the light. If the light is too strong, it will recommend you to use ND 1 or ND2, and the screen will flash.