Plug in your tv then go to play store and type amazon.com/mytv.
Then open your device's app store to download and install the Prime Video app.
Open the Prime Video app.
Then register your device by selecting Register on the Amazon website.
You will be given a code to enter on a given website.
Register your device by selecting "sign in and start watching" to enter your account information directly on your device.
To register your device using a registration code.
Find the 5-character registration code on your device by selecting Amazon Video home screen.
From your computer, go to Register Your Compatible TV or Device.
choose register on the Amazon website to get a 5–6 character code.
Enter your registration code in the text box.
Then code to enter in your account.