Modern SharePoint pages can be configured with three different page layouts,

Home Page Layout

Article Page Layout

Single Part App Page Layout

Below is the PNP PowerShell script to change the Page Layout,

Write-Host "Enter site collection URL:"
$siteCollectionURL = Read-Host
 
Write-Host "Enter page name:"
$PageName = Read-Host
 
Write-Host "Choose the page layout:"
        
Write-Host "1 - Home"
Write-Host "2 - Article"
Write-Host "3 - Single Web Part App"
$choice = Read-Host


if($choice -eq "1"){
    $choice = "Home"
}elseif($choice -eq "2"){
    $choice = "Article"
}elseif($choice -eq "3"){
    $choice = "SingleWebPartApp"
}
 
Connect-PnPOnline -Url $siteCollectionURL  
Set-PnPClientSidePage -Identity $PageName -LayoutType $choice

Summary

In this blog, you learned how to change page layout in SharePoint Online using PNP Powershell. I hope this blog helps :)