Thanks for your question.
Here is our help page on how to upload to Box:
You are part of your company's Enterprise account and so you have a filesize limit of 2GB.
As long as the video you wish to upload is <2GB you should be good to go.
Please let me know if you run into any snags or if there is anything else I can do to help!
And thanks for using Box.
We very much appreciate your company's business!