My first problem: no deleting.

stty echoe
stty erase ^h

This worked!!! Thank you.

My second problem: read only FS.

mount produced

/dev/wd0a on / type ffs (local)
/dev/wd0a on /usr type ffs (local)

ls /etc/fstab gave
/etc/fstab

vi /etc/fstab
gave a page with lots of ~ signs down the left. :wq gave an error about ls
/etc/fstab not existing or something(?).

ls -l /usr/X11R6.1/bin/X etc. revealed X to be a link to Xarm which is a
link to Xarm-27

echo $path produced

/sbin /bin /usr/sbin /usr/bin

typing:

set path="$path /usr/X11R6.1/bin"
and then the echo gave

/sbin /bin /usr/sbin /usr/bin /usr/X11R6.1/bin

whereafter, NO commands worked (ls, stty, you name it - least of all xinit).

Please note, if you tell me to my path or what have you, I might get lost.
It took me a while to figure out how to set the path - and even now I don't
think that I did it right. My UNIX book is more on how to use an existing
system, it's not about setting up a system. Thank you all for your help so
far.