There seems to be no way to turn off the "Dimensions" in the new "Grid tool" where can I find this option or how can I turn those dimensions off?
Under Drawing Settings, the Dimensions are controlled by the Dimension Styles dialog box click on magnifying glass icon in the Dimensions area. Under "View Attributes" you can choose to have "Dimensions" ON or OFF.
To turn Dimensions "ON" or "OFF"
Ahhh... Turn off the grid Dimensions in the reference presentation vs. view attributes Dimensions of the active model.