I've been doing some tests on Sharepoint online and noticed that if I install a Wiki App I can see a new UI in Sharepoint that allows me to easily add new sections and web parts to the page as shown in the picture below:
I tried a similar thing by installing the Wiki App in my local Sharepoint Server (on premises). I went to my team site --> Add new app --> Wiki page library. When I tried to add a new page after installing the Wiki app, it still shows the old Sharepoint UI:
Is there a server update or something I'm missing that I need to install?