I stream Amazon Prime video on my tablet or laptop
I connect my laptop to my TV with an HDMI cable ,
Some videos can be downloaded, but once you start to watch it you have 72 hrs to finish watching, cant start today and finish next week
If the TV is a smart tv with Wi-Fi and apps, you can stream with the TV connected to Wi-Fi, you will Need to register the TV to your Amazon account
To stream you need to be internet connected
With Amazon I prefer streaming instead of downloading
It remembers where I was in the video, if I stop watching and come back another day