Hi Vijay,
> Unable to see the Create button for the administrator user.
Can you please be more specific? Are you saying the "Create" button does not appear in the Portal for ArcGIS website when you're logged in as an administrator? Is this on the Content page? on a web map item page? In the Map Viewer? Can you please post a screenshot(s)?
> if i try to create Hosted feature layer with publisher user, i am getting "Dataset not found" error
Can you please verify that you've deployed a Base ArcGIS Enterprise deployment? So you have the ArcGIS Data Store installed, with a hosting server?
Base ArcGIS Enterprise deployment—ArcGIS Enterprise | ArcGIS Enterprise
Hope this helps,
