Azure Backup gives you a simple, reliable, and cost-effective way to protect your VMs and recover quickly if something goes wrong or corrupted, a solid DR solution to keep you covered until you're ready to move to Azure Functions.

To enable Azure Backup for an Azure virtual machine, open the Azure virtual machine, then navigate to the 'Backups' section and select it.

You can select an existing Recovery Services vault or create a new Recovery Services vault.

You can also create the policy based on your requirements, such as backup schedule, instant restore, and retention of daily backup points. In the backup policy, there are two types of policies the Enhanced policy, which allows you to take up to 4 backups per day and the Standard policy which supports only one backup per day based on snapshot frequency. Once selected, click on Enable Policy.

Reference: About Azure VM backup - Azure Backup | Microsoft Learn