I'm working with Bootstrap and I'm trying to use the bootstrap.min.js script found here.
In my code, if I use the following script tag everything works as expected:
In answer to your title, I have to delve into practices and ways of work.
CDN's (using a script from a link) isn't generally a good idea for development, as you don't have that script when offline and anything relying on that will fall over. However, it saves space (as you don't store the script), and it is quite manageable as well (with regards to directories and building doesn't modify the paths etc.). In development, local files are a good idea. In production, however, it is a good idea to either use minified JS, or CDN's, for storage saving.
In answer to your question body, you have to get the path right (including the file name).
..\ goes to the parent directory to start off with, while
.\ is the current directory. Also, the
<script> reference tag has to be above all usages as the page is loaded from top to bottom. Take those tips and see what the issue is.