Beginner Setup Bitcoin Full Node without GUI
In the very same guide you linked, follow the instructions for the Bitcoin daemon.


  I tried to start the daemon and hope it will download the data but it seems nothing change on H.D. usage so I am guessing it is not downloading. Am I correct?


No, you are not correct. You should check the status of bitcoind itself by using bitcoin-cli to send commands to it. You can use getblockchaininfo to know whether it is actually syncing by calling it twice. If it is syncing, then it will report a different block height and best block hash on the second call.