You must not use /debian/rules
, but instead debian/rules
(note the missing slash at the beginning). If you start a path to a file with a slash (/
), the system will start the search in the root directory of your filesystem (this is the top-most directory on any Unix system). On the other hand, if your path does not begin with a slash, the search will always be relative to your current directory. The latter is what applies to invoking debian/rules
.
The command is supposed to be executed inside an extracted Debian source package. Check if ls debian/rules
will list a file, otherwise you are in the wrong directory.
Regarding a guide for beginners or anything: Debian package building, let alone the creating or modification of Debian packages is decidedly not a beginner's topic. You should first get a solid foundational knowledge in Linux administration before getting your hands dirty in that area.