If you look at the README file inside the noip folder, you will see that, in order to have the No-IP Dynamic Update Client automatically launch at boot on Linux, you have to copy and paste a script inside the relevant
rcX.d folder inside
/etc/init.d. However, Raspbian does not have this folder, so the procedure is slightly different if you are using a Raspberry Pi (you can find some information here).
These are the steps to follow: