Photoshop CC - How To Exit 3D Mode

Follow the instructions below

Exit 3D Mode in Photoshop

When you are done editing your 3D object in Photoshop, navigate to Window > Workspace > Essentials. This will reset your Photoshop CC windows back to default. To eliminate these 3D options and grids, right-click the object in your layers window and select Render 3D layer.

Photoshop > Window > Workspace > Essentials