To display the $ Bash or shell prompt symbol at the start of your code snippets with Hugo, you need to add some CSS. This will also cause the cursor to ignore the $ symbol when someone wants to copy the content of the code snippet block, which is a nice bonus.

code.language-bash::before {
    content: "$ ";

If you then create a code snippet with the bash syntax…

echo 'hello world' && exit 1

…It will look like this:

echo 'hello world' && exit 1

Note: This will only show the symbol at the first line of each code block that has the bash syntax assigned:

echo 'hello world'
exit 1