1. Firstly, go to the product on the admin console that you to add a video to: PRODUCTS>*product name*.
2. Scroll down to the Image Options section, below the images, you will see a "Video" tab.
3a. You will need to upload the video to either YouTube or Vimeo. (please note: you can't upload a video file directly onto the site, it must be done through one of the aforementioned services)
b. To the left is a drop-down menu which is set to "None" by default. Change this to either YouTube or Vimeo depending on where the video is uploaded to.
c. To the right, you will see a textbox for a link to go in. In here, enter either the YouTube or Vimeo URL / website address, this will be in the top search bar on your browser. e.g. https://www.youtube.com/watch?v=n_uFzLPYDd8 or https://vimeo.com/826701301
(Please note: YouTube Shorts aren't the same as YouTube links and therefore can't be added)
d. As normal, click save and the video will be added to the product.