By Looking at your example. in my opinion its not targeting problem to solve rather related to
- live chat or bot chat which has to be triggered based on ideal stage of user on page (these features available on their side)
- or can be a custom javascript code on page
(target will be hard and too much of work to track the current session timing on page at client side)
if you search web, you can find plenty of options to do model pop up based on defined times.
note: adobe analytics can help you get better understanding of time spent by users on page