This worklet will help migrate 32-bit version of Microsoft Office to 64-bit version.

Need to download Release history for Office Deployment Tool (ODT) - Office release notes | Microsoft Docs and open to get a copy of setup.exe

Next create an XML file called configuration-Ofice365-x64-MigrateArch.xml

<Configuration>
  <Add OfficeClientEdition="64" MigrateArch="TRUE" Channel="Monthly" AllowcdnFallback="TRUE">
    <Product ID="O365ProPlusRetail">
      <Language ID="en-us" />
    </Product>
  </Add>
   <Display Level="None" AcceptEULA="TRUE" />  
  <Logging Level="Standard" Path="C:\windows\temp" /> 
</Configuration>

Upload both setup.exe and configuration-Ofice365-x64-MigrateArch.xml to the worklet.

Evaluation

$workdir = "C:\ProgramData\Amagent\O365"
IF(Test-Path $workdir){ Remove-Item $workdir -recurse -force | out-null }

$scriptblock = {
    Get-ItemProperty HKLM:\SOFTWARE\Microsoft\Office\ClickToRun\Configuration -Name Platform | Select-Object Platform
}
# Run the scriptblock and store results in the $64bit variable
$platform = & "$env:SystemRoot\sysnative\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass -WindowStyle Hidden -NoProfile -NonInteractive -Command $scriptblock

IF($platform.platform -eq 'x86'){
    Exit 1
}else{
    Exit 0
}

Remediation

$scriptblock = {
    Get-ItemProperty HKLM:\SOFTWARE\Microsoft\Office\ClickToRun\Configuration -Name Platform | Select-Object Platform
}
# Run the scriptblock and store results in the $64bit variable
$platform = & "$env:SystemRoot\sysnative\WindowsPowerShell\v1.0\powershell.exe" -ExecutionPolicy Bypass -WindowStyle Hidden -NoProfile -NonInteractive -Command $scriptblock

IF($platform.platform -eq 'x86'){
  # Setup Working Directory
  $workdir = "C:\ProgramData\Amagent\O365"
  IF(!(Test-Path $workdir)){mkdir $workdir | Out-Null}
  # Copy setup files
  Write-Host "Setup working directory at $workdir."
  Copy-Item configuration-Office365-x64-MigrateArch.xml $workdir | Out-Null
  Copy-Item setup.exe $workdir | Out-Null
  # Migrate Office from 32-bit to 64-bit
  Write-Host "Running Command $workdir\setup.exe /Configure configuration-Office365-x64-MigrateArch.xml."
  Start-Process "$workdir\setup.exe" -ArgumentList "/Configure configuration-Office365-x64-MigrateArch.xml" -Wait

}else{
    write-output "Detected $($platform.platform) as installed. Not running." 
}