How can I see general traffic usage? What employees are doing at work

Hi,
I’m trying to figure out if I can somehow use the tools available in routeros to create a graph or a simple report either weekly or monthly in which we ca see what websites are the most accessed ones and maybe time spent on. The boss suspects employees spend most of the time on Facebook and or other social media websites during work hours. I’m looking for a simple way, not necessarily permanent so trial solutions if exist are welcome. Maybe some logging server in Amazon aws or to an the graphing tool already in routeros do this? If yes, a tutorial would be awesome.

Thanks!