How do I require another module from a different directory without having path issues?

For example, src/index.js, has a require('../other/main') statement

Oh, there's an error, because in the main.js JS file, there are things like getting files from paths, and it's just a path issue. (e.g. ./SOMEFILE won't work when it's clearly in that other directory path)

But, if I individually on my CLI, to cd other, and npm start (or node main.js), no path issue.

How do I require without having to cd into the directory to make the path work?

But I don't get it, how do I just easily require a JS file but from another directory with a package.json or whatever?