How to create custom metric for redis

I setup redis by helm and enable metric

i flow document https://rancher.com/docs/rancher/v2.x/en/project-admin/tools/monitoring/#project-metrics
A Redis application is deployed in the namespace redis-app in the project Datacenter. It is monitored via Redis exporter. After enabling project monitoring, you can edit the application to configure the Advanced Options -> Custom Metrics section. Enter the Container Port and Path and select the Protocol.

I can’t find configure “Advanced Options > Custom Metrics” same document
I found Custom Metrics in workload pod. but how is ’ No Endpoints’ mean ?