How to be MEAN?

During the spring and summer of 2019 I had the occasion to study some web development, including Angular and some Node.js.

But I feel that is just the beginning... one of the directions I would like to deepen this is to do some more realistic tutorials and apps in the MEAN stack.
M = Mongo DB, I already use this for some of my tutorials , I hosted some sample DB here: https://cloud.mongodb.com/
E = Express.js, which is a web framework within Node.js
A = Angular
N = Node.js, which I studied for 1-2 month during summer of this year.

Currently I don't have the time for this stack, so I put it on hold...
Still, Angular+Firebase, Angular+Material design and Node.js + Mongo.DB is something I want to check out in more detail than before. Perhaps an idea for 2020 :) I have too many ideas already!!! Can somebody help to prioritize? Maybe this is being MEAN?