How to collect remote server statistic data

Dear All:
I am absolutely new in Grafana, I am lost with how to obtaining remote server stats data now. I configured my Grafana with data source MySQL and saved the config data but I could not see any tables in the MySQL DB also it seems no any details could be find from the Grafana web site how to obtain data from remote server to make the graph(s)? I think there should be an agent to be installed in the remote server to collect data ? but which tools/apps should be used for this purpose ?

Thanks in advance.