Welcome to the community, @Nick_Peacock-Smith!
Oddly enough, you can’t trigger an automation with a button being clicked (go figure), but you can do it with a checkmark being checked.
Please add your feature request into the #show-and-tell:product-suggestions category, and hopefully they can add this functionality in the future.
A button being clicked can run a script via the script app, but that is usually a dealbreaker for most people because it opens up the apps sidebar, and visually runs the script on the user’s screen. So it’s not really a valid solution for most use-cases.
Thanks for your response @ScottWorld. I actually am not having an issue triggering the automation. The issue is that I can’t insert the date of when the button was pressed because I can’t get a “last modified date” based off when the button is pressed. Is that correct?