Hello Anusha,
Sorry for the late answer.
Regarding the Grafana dashboard, this is a known issue. You can import the dashboard manually. You can find OSM dashboards in devops repository in /installers/docker/grafana folder. The dashboards you need to import are: osm-sample-dashboard.json and osm-system-dashboard.json.
And regarding the status of mon-k8s, it takes some minutes to the pod in order to be available. In case, the issue persists, then try the following commmand that will restart the agent:
microk8s.kubectl -n osm delete pods mon-k8s-operator-0 --force --grace-period 0
I hope this helps.