I'm having trouble finding a way to add the dvr and firestick(HDMI) app. I have roku premiere and in the settings it do not have the "tv input option" so what is an alternative way that I can add this?
Not certain what you mean. A Firestick is an Amazon streaming device. If you want to use one, you would connect it to another HDMI input on your TV. Same with a DVR.
A standalone Roku device is just that, standalone that connects to one of your TV's inputs. You don't connect other devices to it.