A few years back, this all worked fine in Google Chrome, but not anymore. It now intentionally blocks autoplaying videos that have audio.
In addition to the old MSIE browser, the current version of Firefox allows autoplaying video with sound on page load.
There used to be some workarounds and advanced setting overrides in Google Chrome, which you’ll find with most web searches on this topic, but they no longer work in recent versions (I think since ver 81). The trick is autoplaying anything with audio will not work until the user interacts with the page and then autoplaying will work. So, depending on your requirements, you might be able to force the user to do something on the page and then load a video into an object on the page and it can autoplay in the Google Chrome browser. This cannot work with loading a video into an inline frame because the page in the inline frame is a separate browser instance from its parent page.
Here is a demonstration of various methods for getting video to work in Axure. Take a look at the Video with fake autoplay and DP page for autoplaying after interacting. It is not so much “fake” autoplay as it is enabling autoplay by first requiring the user to do something on the page.
Video-Examples-3.rp (302.1 KB)