Finding Zero Point

I recently acquired expensive espresso equipment as someone with no experience so I am currently way over my head with it. I have had a lot of trouble with grinding fine enough to pull a proper extraction, as I have been worried about setting my dial below the zero reference point.

Is finding the zero point a standard practice? I assumed that the zero reference point would have been calibrated in the factory, so is it not uncommon for the true zero to be potentially far below the 0 reference point? I have not been able to find many grinder set up vids (especially for my grinder) so I am confused as to how confidently I should be dialing the grinder below zero.