Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
If you use Outlook, then install Office 2019 first so that you can import your Identity/Profile information into Outlook from 2011. Once you're satisfied that all your calendar, contacts, tasks, email, etc has been brought forward, then you can uninstall Office 2011.
If you use VBA to make or edit UserForms, keep Office 2011 until that feature has been completed in Office 2016.
Unless you have a nearly full drive, I suggest keeping 2011 around until you feel confident that you can do everything you need to in 2016. The two versions do not interfere with each other at all. You can remove 2011 at your convenience.
I'm a bit confused. Are you advocating keeping all three Offices, or is 2016 a misprint?