Did you mean tracking employees time and billing it to a vendor? If so, that isn't currently an option in QuickBooks Online. To learn more about time tracking in QuickBooks Online, you can check out this article: Set up time tracking.
If you wish to have this option added to future product updates, I recommend sending your suggestion straight to our Developers. To do so, simply go to the Gear icon and select Send Feedback Online.
However, if you mean something else, please let me know. I'm always here to help. Have a good day.