First of all – legs. Owls have massive talons and strong legs because they catch prey with them. Frogmouths on the other hand prefer using beaks to catch their meal.
What else? Nesting. While frogmouths builds their nest in tree branches, owls nest in tree hollows.
They also have different beaks. Frogmouths have wide pointed forwards, owls have narrow, downward pointed ones. Owls also have large face discs and asymmetrical ears which are not present in tawny frogmouths.
