Almost all UNIX shells do tab completion by default. If you want shorter equivalent commands just create an alias for the ones you use commonly.
The problem with tab completion is that there are so many commands in UNIX that you tend to need to type in many more characters than you would in IOS before the command prefix becomes unambiguous.
FWIW, on my
tcsh setup, typing
tel<tab> offers me
telnet. Only once I type
n does it them autocomplete to the latter of those.
Furthermore, some shells can then offer you command line arguments too, so long as it has been told in advance which arguments are valid for the current program.