Unfortunately, VS Code doesn't have such a feature. It would require it to detect what you want to do, and whether or not you want to write HTML Code in that JavaScript file. However, there are two workarounds (afaik):

1. You could create a new temporary HTML file, write it there, then copy+paste it into the JS file (and escape end of strings etc.) OR
2. You could install GitHub Copilot (however this does send your code to GitHub servers)

Hope this helps!