opening CAD model in Unity3d

i am trying open heavy CAD file in unity3d With polycount of 83,192,985 although it is able to load this heavy model after copule of hours but i cannot navigate the model such as rotating
clicking on the child for information etc…is there any way around for navigating model or i just need to reduce the polycount to achieve mentioned desired result.

You’re definitely gonna need to reduce the poly count.

At the very least, you want something that’s under a million