I really want to know how to create a dashboard on ArcGIS online from scratch please help.
Well, the first step would be to publish a web map in AGOL and configure your pop-ups and symbology before creating the dashboard. In the Map Viewer click Share, then click Create a Web App, and then click Operations Dashboard. From there you can add all the widgets you like.
Check out this website:
What is a dashboard—Operations Dashboard for ArcGIS | ArcGIS
And watch this video:
Operations Dashboard for ArcGIS: An Introduction - YouTube
Thanks Miguel for your response
Some other useful resources to help you get started,
Hope this helps,
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