Are node.js, express,, localhost on http, and alike ACTUALLY secure? [closed]

I use localhost for learning more coding, and I keep wondering the same question over and over again when I use Node.js:

Is it really safe?

Many, many people might have asked this. I would naturally want to put SSL HTTPS encryption on it, but there isn’t really anywhere you can get it, even if it may be a bit overkill.

It feels like there should and could be some "protection" or "encryption" type package for npm or something.

I haven’t used Node.js or localhost it for sensitive information, but should I be worrying about this?