It sounds you’re interested in performance monitoring. See if this helps. Here’s the deep dive recording. It’s a bit dated and I think @ehelms planned to update that and perhaps include grafana, not sure if there’s some progress already. There’s also this tutorial.
If you’re more interested in Foreman’s health, e.g. how many tasks are stuck or how many hosts are in red state, it was discussed at this thread Monitoring Foreman with Prometheus via statsd.
Hope that helps.