Out of the box features for creating webpages, forms, workflows.
To be able to work with Business Connectivity Services, Master Pages,
Apps, Page Layouts, Web Parts, Windows Workflow Foundation, SharePoint Ribbon, etc.
SharePoint Object Model (OM)
SharePoint Designer
Workflows
Visual Studio / C#
Power Apps
REST API & JQuery
Javascript, HTML, CSS
Visio (good to have)
InfoPath (good to have)