A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Hi Uday Singha,
I go through the post carefully, as for the questions, here are my answers:
Question #1:
You may not migrate SharePoint 2010 workflow to SharePoint 2013 workflow, as they are majorly different. So you may need to rewrite it. You may also check the thread on discussion on such topic: How Migrate SharePoint Designer Workflow 2010 to 2013 (microsoft.com)
Question #2:
SharePoint workflow is retiring, so instead of using SharePoint Workflow and edit them with SharePoint Designer, it is better to migrate to Microsoft Power Automate. Check the link for more information on guidance of migration: Guidance - Migrate from classic workflows to Power Automate flows in SharePoint | Microsoft Docs, For more information on SharePoint workflow retirement: SharePoint 2010 workflow retirement - Office Support (microsoft.com)
Question #3:
As you can see from the link: SharePoint 2010 workflow retirement - Office Support (microsoft.com), SharePoint 2013 workflow is still supported but will be retired at some point in the future. However, there could be no exact retirement date now.
Hope these can help.
Regards,
Clark