Airtame is a device that is capable of streaming video files from your computer to external screen. You can see more information here: Audio & video streaming
However, various factors need to be considered. If streaming movies is the main use-case, perhaps, Airtame is not the right device. It is designed for business/education oriented environments where main focus is presentations, occasional videos and similar use-cases related to meetings and classes. In case watching movies is the main use-case, there are other devices that can do this more conveniently.
Airtame to run a video as digital signage
If you want Airtame to present a video or several videos in a loop, this can be done by configuring Airtame to present a URL as background.
Learn how to do this: How to use Airtame as video signage