In case anyone is curious and is having the same issues that I was having, I decided (and found out how to use) the web installer.
Once you've cloned your copy of the repo of NodeBB and snatched your dependencies -- go to your directory that you've copied the repo to.
use: "ls -la" to make sure you can see the "loader.js" file -- now what you're gonna want to do is use "nodejs loader.js" (we use nodejs because ubuntu has conflicts and needs to use nodejs to avoid said conflicts).
The first time I ran the web installer it did not like my personal inputs for the db name and password and even name of the database - so for the 2nd time, after I selected to use "MongoDB" for the database, I left the rest blank.
This worked.
Hope this helps any others!
p.s. -- if anyone knows readily where the mongodb database files are being stored for nodebb, that'd be helpful!