After importing a DWG, I can not see my model

No, that just replicates all the excessive detail.

You probably need either to find a low poly model of a similar object, or redraw on top of the one you have, using fewer segments in arcs, replacing finely draw detail with one or more images, reducing the size of any over-large textures in an image editor, and various other techniques suggested elsewhere.

Then delete the original over complex component and Purge the model to get rid of the component definition.

Here’s a thread I started a few years ago. Some of this may help you understand how to reduce the size and over-detailed parts of your model.

FWIW, Dave’s link no longer works (says the file is deleted) and when I download and view your original, using Camera/Perspective and Zoom Extents all I get after several minutes is a blank white Sketchup workplace screen.