How to get the group members of a sub site in SharePoint online using CSOM

Question

I have a requirement to retrieve the members of a specific group ( This is a custom SP security group) in a subsite using CSOM. Please let me know how I can retrieve a specific security group using its name and get it's users in SharePoint online. I found multiple solutions which get the users of a site collection but I need it for a sub site. The client context in my case would look something like below -

https://abc.sharepoint.com/sites/applications/xyz/123456 ( where 123456 is a sub-site within the site collection xyz and need members of '123456 Owners' group)

Appreciate all your help. Thank you in advance.