@Rajendar Chakinala While we don't have a readymade sample PS script to achieve this, you can put together your own script with the help of below links:
Query VMs not configured for backup by running an ARG query in PS: Sample query https://learn.microsoft.com/en-us/azure/backup/query-backups-using-azure-resource-graph#list-all-azure-vms-that-have-not-been-configured-for-backup
Configure backup for VMs using Azure Backup PowerShell cmdlets: https://learn.microsoft.com/en-us/azure/backup/backup-azure-vms-automation
Note - If you are interested in using Azure Policy to meet the same requirement, we have built-in Azure Policies available for those: https://learn.microsoft.com/en-us/azure/backup/backup-azure-auto-enable-backup
Hope this helps!
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