What you describe, I believe, could be done without Javascript. At least if the “asks the user for tags” is just a text entry field.
Start an action with a Prompt action step with “Include Text Field” set to true to prompt the user to enter a list of tags.
Follow that up with a “File” action step that writes the content to the right place in your Obsidian vault…you can start with one of the File-based example actions above in this guide.
Then modify the template use for the body content in the File step. It could contain the front matter, creation date, and input from the prompt with template tags. See this article to get started on how template tags work.