Too Long; Didn't Read
Agile Metrics are an umbrella term for metrics that deal with the underlying agile methodology your software team is probably already using. They can be derived from a visible board with each column describing one state of work (Backlog, Committed, In Development, Approval, and Released are my starting recommendation). You can also derive these metrics from backlog management software like Jira, Trello, Clubhouse, and others. Engineering Metrics tell us another story: how work is being done internally to meet the requirements of the agile process.