04-14-2020 Ken

Since Linux does not have a "cls" command that Windows/DOS
does have do this once

sudo ln /usr/bin/clear /usr/bin/cls

Then in your bwbasic 3.20b program to clear the screen use
SHELL "cls"

Or at the start of you bwbasic 3.20b program include
OPTION TERMINAL ANSI
then CLS will work