To achieve this requirement create a simple list in SharePoint.
Connect this list (SimpleList) to PowerApps using SharePoint Connector.
Then Add Three Screens.
In the first Screen Drag Edit form control and assign the data source as “SimpleList” then it will add all the columns onto the form. In the first screen keep the columns we need and remove other columns so that we can add those other columns in next screens.
In other screen forms 2 and form 3 : Item property we need to add Defaults(SimpleList) to remain connected with first form.
In the final Submit button OnSelect write the code.
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