A couple different things you could do that I can think of…

  1. Install the free classify plugin and add CSS to make a regular group behave as a floating group (requires some knowledge of CSS)

  2. Install the paid plugin by BDK which is a floating group plugin to allow you to turn any element into a floating element.

The reason you are having a hard time with this setup as you are trying it, is because it is impossible (at least from my frustrating weeks spent trying to do similar) with a floating group element provided by Bubble because that floating element is ‘connected’ to the page and is not capable of being contained by other elements except the page and therefore can not be ‘connected’ to other elements on your page.