You can learn Prometheus from the following blogs and youtube videos
Create seperate namespace
kubectl create namespace monitoring
Install Prometheus operator using helm charts
helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
helm repo update
helm install prometheus prometheus-community/kube-prometheus-stack -n monitoring
Portforward the request to the service
kubectl port-forward svc/prometheus-grafana 3000:80 -n monitoring
Visit localhost:3000 and access your Grafana dashboard