Open a terminal, then:
docker compose up
Use -d to start detached from terminal
Then Open with a browser: http://127.0.0.1:9090/ to see Prometheus UI
To see some data you can use autocannon, e.g.:
autocannon -c 10 -d 10 http://127.0.0.1:3042/next
Then you can query Prometheus UI, e.g.:
http_request_summary_seconds{serviceId="next"}