Hello cromaticx, welcome to LQ and to Linux,
as per our forumrules we don't do each others homework. It would be necessary that you tell us for each of your questions what you already have found out.
There is a very helpful tutorial through the first steps http://rute.2038bug.com/index.html.gz
you will find the answers there.
For Linux/Unix commands and the shell(s) there are the so called manpages. If you don't have a Linuxcomputer available, you may also google for "man ksh" which leads you to the manpage for the kornshell.