http://prntscr.com/7uq11x

So as you can see on the image I want that place to be the respawn of the cube, and go on the path that the arrow is showing.

I saw an video of how to manually create droppers, but it still does not explain how to move cubes through the vacum tubes.

And while I'm here, I wanna ask how do I do that with other vacum tubes too? (Like navigating through the vacum tubes of aperture science, if you know what I mean).

Thanks guys

You'll need a point_template of the cube at the intended spawn point, which you can then use to create new ones (via the ForceSpawn input). A trigger_push will then send them into the map.