Access from another application bypassing login

I want access ERPNext’s CRM Module from another application without login. For testing, I tried to access from my local installed ERPNext to access cloud server ERPNExt.

I create a button called Live App in my local ERPNext. On click the button I want to open server installed ERPNext without login.

For this I think I need OAuth. But I never use OAuth before. Any insights, best practices, or step-by-step instructions pertaining to OAuth implementation within the context of ERPNext would be greatly appreciated.