I’m not really sure how you would be able to write an interpreter without a parser, since you need to know what the user is trying to do. For a more complete tutorial there is Make-A-Lisp (mal) [0] that has steps for making a lisp in various (including JavaScript) and has a process guide [1] to get started.
[0] https://github.com/kanaka/mal
[1] https://github.com/kanaka/mal/blob/master/process/guide.md