#!/bin/bash
OPTIONS="Hello Quit"
select opt in $OPTIONS; do
    if [ "$opt" = "Quit" ]; then
     echo done
     exit
    elif [ "$opt" = "Hello" ]; then
     echo Hello World
    else
     clear
     echo bad option
    fi
done
		

#!/bin/bash
if [ -z "$1" ]; then
    echo usage: $0 directory
    exit
fi
SRCD=$1
TGTD="/var/backups/"
OF=home-$(date +%Y%m%d).tgz
tar -cZf $TGTD$OF $SRCD
		

In many ocations you may want to prompt the user for some input, and there are several ways to achive this. This is one of those ways:

#!/bin/bash
echo Please, enter your name
read NAME
echo "Hi $NAME!"
		

As a variant, you can get multiple values with read, this example may clarify this.

#!/bin/bash
echo Please, enter your firstname and lastname
read FN LN
echo "Hi! $LN, $FN !"