Form start timestamp

I've created a web form that will be heavily utilized. Managers are wanting to conduct a transactional analysis to see how long it takes the worker to complete. I'm looking for a way to capture the current time either when the form was accessed or find a shortcut to copy from the operating system and paste into the first visible field in the form. While O365 products have a hot key combination, it appears Windows 10 does not saying it relies on applications to provide that capacity. Any help would be appreciated.