If your asset is oriented strangely or the camera navigation feels unusual, the coordinate system needs adjusting. Open the asset and click on the Edit Mode button ( - Top Center). Then, within the left panel's View Options > Coordinate System section, press each of the X-up, Y-up, or Z-up buttons until your asset appears upright and the view navigation feels natural.
Once you're happy with the result, click the Save button ( - Top Center) to preserve your Coordinate System change for future viewings of the asset.
Finally, click on the Set Starting View button ( - Top Center). This will ensure your asset thumbnail and initial camera view uses your corrected orientation.
Note, in some extremely rare situations, you may need to adjust the Rotate X, Y, and Z sliders instead of using the X-up, Y-up, or Z-up buttons.