For detailed instructions on how to create a site-to-site VPN connection in the Azure portal, please refer to https://learn.microsoft.com/en-us/azure/vpn-gateway/tutorial-site-to-site-portal
I don't know what are the requirement for a VPN Site-to-Site on IBM Cloud, but, in the documentation in step 5 on the Create VPN Connections (https://learn.microsoft.com/en-us/azure/vpn-gateway/tutorial-site-to-site-portal#CreateConnection) is where you will ajust the configuration
Hope this helps!
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