You are wrong , it is really easy. You can do what I said and it's works.
This is the template you want.
data - Momentjs - YYMMDD.md (46 Bytes)
Moreover, for date/time you can use this sort of template, but you can do any template you want putting the text you want to insert in.
For example I use template for fast inserting style tags in my notes, (see the attached file)stile.md (90 Bytes)
Others example here: GitHub - WinkoErades/Joplin-note-taking-templates: Joplin note taking templates
What you need to know from moment.js is only the string format it accept. See tables under this paragraph: Moment.js | Docs
Edit .md files:
Last thing: edit md file does not require Typora (that also is a good markdown editor). A markdown file is a plain text file. You can edit it with notepad (or any plain text editor like VS Code, Vim, Notepad++, etc etc) and then save with the .md extension (if you save it ad .txt you can simply rename it and change the extension).
Hope this was useful.