Hi Prasuna kakani, it is a pleasure to be able to help you.
Per my knowledge, workflows created with SharePoint Server can be migrated to Power Automate using the SharePoint Migration Tool (SPMT).
You can refer to the documentation: Migrate SharePoint Server workflows to Power Automate
And this is an article about migrate InfoPath forms from on-premise SharePoint to SharePoint online for your reference: http://www.sharepointjunkies.com/migrate-infopath-forms-sharepoint-2013-sharepoint-online/
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