Hi Deleted,
Certainly as an Admin their are many chances to create and distribute custom content! Leveraging Stream in combination with tools like PowerPoint Recording can enable you to create quick "Show Me How" videos that you can distribute. You could also create your own custom emails to either vetted pre-existing training content (from https://support.office.com/en-us/office-training-center ) online or mix between pre-existing and custom content. You could then aggregate all this via SharePoint Online for your users. If you don' want to build that out you might consider waiting for the upcoming Microsoft Training Services (see https://techcommunity.microsoft.com/t5/Microsoft-SharePoint-Blog/Introducing-Microsoft-Training-Services/ba-p/195732 ) Hope this helps. If you want to see some concrete examples let me kow what kind and I will be happy to put together a quick video or two for our blog here.
Thanks!