The part before the $ in a shell is called prompt. It can be configured by changing the variable
$PS1. There are is a similar question with good answeres.
The man page (see "Bash" and there "PROMPTING") says:
\w the current working directory, with $HOME
abbreviated with a tilde (uses the value of the
\W the basename of the current working directory,
with $HOME abbreviated with a tilde
So you have to change
\W. Probably the initial value for $PS1 is stored in your
.bashrc, that means you have to edit the file
/home/YOUR-USER-NAME/.bashrc and you will find lines similar to:
if [ "$color_prompt" = yes ]; then
unset color_prompt force_color_prompt
\W in both lines and open a new terminal.