Hello @Gongya Yu ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you would like to know if there is a way to stop Azure VPN gateway, when it is not needed or used.
As of today, there is no feature available to stop/start Azure VPN gateway. So, the only option is to delete and recreate the gateway.
This feature ask is already under review for global release but no ETA as of yet. You can upvote the feature in the below feedback forum:
https://feedback.azure.com/d365community/idea/4a70d8e3-8926-ec11-b6e6-000d3a4f0789
The only workaround that I can suggest is that you could delete the resource group using PowerShell/CLI and automate the VPN gateway creation via ARM templates or Bicep (considering the time required to create the resource).
https://learn.microsoft.com/en-us/azure/automation/automation-deploy-template-runbook
Kindly let us know if the above helps or you need further assistance on this issue.
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