Yes. I drew it with the back faces out. The green is my style’s back face. I made the “hole” a component to make it easier to handle. The ends of the cylinders on either side coincide with the inner and outer surfaces of the box. After placing them inside the box walls, I exploded them and then deleted the faces skinning the holes.
X-ray is a face style. See View>Face Styles. I didn’t use X-ray, though, because I didn’t want my hole component to be transparent. I painted a transparent material onto the faces of the box.
I would suggest you abandon TinkerCAD if you’re going to work in SketchUp. Your model needs a lot of help before it’s even close to ready for printing. There’s a lot of garbage geometry that needs cleaning.
To be printable, you’ll need to make a component or group of the geometry and SketchUp needs to show the component or group as solid.
