Hi @Harish Patil ,
Per my test, you could follow these steps:
Download SharePoint online management shell
Then run the command:
Install-Module SharePointPnPPowerShellOnline
And connect your site:
#Connect to the classic site with pages to modernize
Connect-PnPOnline -Url https://contoso.sharepoint.com/sites/teamsite
Like this:
Then run this command, you will see a new modern page, and then set it to Home page:
ConvertTo-PnPClientSidePage -Identity Home.aspx -AddPageAcceptBanner
Reference:
Transform Classic SharePoint Pages To Modern Look And Feel
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