I suppose that the time signature is Common Time (= 4/4) - right?

1) To make the change “globally” (= everywhere in the entire Finale document):

Document menu > Document Options > Beams

Take a good look at the beaming options in the upper pane:

- Beam Four Eighth Notes Together in Common Time

- Include Rests when Beaming in Groups of Four

- Beam Three Eighth Notes Before/After an Eighth Rest

When you have changed the beaming options, all new notes will be beamed according to the new settings.

To update already existing notes, select them, and use

Utilities menu > Rebeam > Rebeam Music

2) To make the change “locally”:

Simple Entry Tool.

Select the note after the desired beam break.

Simple menu > Simple Edit Commands > Modify Entry > Break/Join Beam (pay attention to the keyboard shortcut, and remember it)

or, in the Speedy Entry Tool:

Speedy menu > Speedy Edit Commands > Break/Join Beam (pay attention to the keyboard shortcut, and remember it)

Thank you very much. 

Det virker. :-)