Add connections in doctype

I need to add the “Opportunity”, in menu connections, follows the image below:
can someone help me?

You need to add the doctype connection in
project must be linked with opportunity

'label': _('CRM'),
'items': ['Opportunity']

I am trying to connect projects in opportunity, but it is not working, I am using the following code in


‘label’: _(‘Project’),

‘items’: [‘Project’]