when you insert a CAD drawing, you have the option to keep the original colours or override it with black and white, invert, etc.

if you want to hide the attachment itself: go to visibility/graphics > imported elements, and uncheck the cad instance;

if you want to hide specific layers in the attachment: go to visibility/graphics > imported objects, open the cad instance tree and uncheck only the required layers;

if you want to change the colours of the cad instance's layers: go to manage > object styles > imported objects, open the cad instance tree and change it's colours/line weight;

if you want to hide the cad instance in all views: go to manage > manage links > CAD Formats, unload the CAD instance;

Those are the main options I can think of now