Is there a way to take a text field and place a container field in the middle so it "floats" with the text? Like a letter with a signature in the middle? PLEASE HELP!

If you want the container to move around to the right position when a document is printed, this can be done by positioning it on a layout with separate text fields before and after it (and also alongside it if desired) and using the format sliding/printing dialog to make the objects move around and shirink up to take up any unused space.

If you simply want to superimpose, you can place the container in front of (over the top of) a text field - but it will not be embedded in the text in the way a 'floating' graphical object is in some word-processing and layout applications.