What is the comfortable Linux OS for offline use or use without internet connection?
There is no reason why a Linux OS (of any distro) can not be
used without an internet connection. Provided that either an Linux
type OS is downloaded and written as an IOS on a CD (for one
example) to be used as a live CD with the options of trying or
installing. Or you have been given the install disk, so not needing
the internet! There are many operating systems and therefore, many
opinions on what distro is the "best"! Have a look at Linux Mint or
Ubuntu - my choice!