There's an old saying: "Just because you can do something doesn't always mean you should."
Yes, you can spin a round filter onto a lens and then, assuming the filter has threads on the inside of the front of the filter ring, spin the square filter holder's adapter to the front of the filter and attache the square filter holder in front of the round filter.
Unless you're using a fairly long focal length lens you will almost certainly have to deal with fairly significant vignetting in the corners and maybe even edges of the camera's field of view.
Most 'thin' spin-on filters do not have threads on the inside of the front of the ring, so you'll likely need to use a regular instead of a 'thin' round filter. The thickness of the adapter ring for the square filter holder can also have an effect since it reduces the inner diameter of the front of the round filter's front ring.