@WinTechie Thanks for reaching out to Microsoft Q&A, apologize for any inconvenience caused on this.
To Configure the Platform settings like platform (changing bit size of worker process) you can use any of the below PowerShell cmdlet or AzCLI cmdlets to achieve this.
Power Shell Cmdlet :
Set-AzWebApp -ResourceGroupName <group-name> -Name <app-name> -Use32BitWorkerProcess $True|$False
AzCLI Cmdlet :
az webapp config set --resource-group <group-name> --name <app-name> --use-32bit-worker-process [true|false] --web-sockets-enabled [true|false]
Refer to this documentation about how to configure general settings in app service.
Feel free to reach back to me if you have any further questions on this.