No, as UltraVPN doesn’t have a dedicated app for Fire Stick devices. You also can’t manually configure it on your router to use it on your Fire Stick, as the provider doesn’t support manual router setups either.
If this is an issue for you, try ExpressVPN instead. It has the best Fire Stick app on the market (it’s super easy to navigate with your remote), it provides blazing-fast speeds, and it also works with 100+ streaming platforms.