You can read user input as a variable.

For example:

read name

will save what the user entered and save it as a variable called name.

You can ask a question first, like so:

echo "What's your name?"
read input
echo "Your name is: $input"

By default, it’ll ask for input on a new line. You can supress the new line with -n

You can use read instead of $1. So instead of

foo.sh Aamnah
echo "Your name is $1"

where you are passing my name as an argument, you can prompt me for it, like so:

foo.sh
echo -n "What's your name?"
read name
echo "Your name is $name"