I guess the root problem here is the packages themselves. I don't think there
really is a problem though. Some packages are intuitive to use, e.g.
graphical in nature and insert a menu item when installed. The others one
just has to figure out how to use.
Most packages come with manual pages of varying usefulness, usually a man
page for each command. Also other documentation is often included, like
configuration examples. Especially packages which are meant to be used via
the command line normally come with a fair amount of docs.
One useful command to list package contents (of installed packages) isdpkg -L
packageFor example the read-out for the package feh (an image viewer) is
/.
/usr
/usr/share
/usr/share/man
/usr/share/man/man1
/usr/share/man/man1/feh.1.gz
/usr/share/man/man1/feh-cam.1.gz
/usr/share/man/man1/gen-cam-menu.1.gz
/usr/share/doc
/usr/share/doc/feh
/usr/share/doc/feh/AUTHORS
/usr/share/doc/feh/README
/usr/share/doc/feh/examples
/usr/share/doc/feh/examples/buttons
/usr/share/doc/feh/examples/keys
/usr/share/doc/feh/examples/themes
/usr/share/doc/feh/README.Debian
/usr/share/doc/feh/copyright
/usr/share/doc/feh/TODO.gz
/usr/share/doc/feh/changelog.Debian.gz
/usr/share/feh
/usr/share/feh/fonts
/usr/share/feh/fonts/black.style
/usr/share/feh/fonts/menu.style
/usr/share/feh/fonts/yudit.ttf
/usr/share/feh/images
/usr/share/feh/images/logo.svg
/usr/share/feh/images/menubg_aluminium.png
/usr/share/feh/images/menubg_aqua.png
/usr/share/feh/images/menubg_black.png
/usr/share/feh/images/menubg_brushed.png
/usr/share/feh/images/menubg_default.png
/usr/share/feh/images/menubg_sky.png
/usr/share/applications
/usr/share/applications/feh.desktop
/usr/bin
/usr/bin/feh
/usr/bin/feh-cam
/usr/bin/gen-cam-menu
/usr/lib
/usr/lib/mime
/usr/lib/mime/packages
/usr/lib/mime/packages/feh
/usr/share/man/man1/gen_cam_menu.1.gz
/usr/share/doc/feh/ChangeLog.gz
Therein among other things we can see manual pages (/man/), some extra docu
(/doc/) and the binaries or executables it comes with (/bin/).
One reads the manual page using man, e.g.man feh-cam
The other (plain text) docu can be read using any text editor, e.g.less
/usr/share/doc/feh/examples/keys
