How do I get better?

Sure; that is partly what the chess community is for - improving at chess

You can always feel free to message me, but learning chess opening principles is a good way to get started. 

https://www.chess.com/blog/KeSetoKaiba/opening-principles-again 

There is also a lot of value in learning the endgame well and reverse-engineering the game of chess. If you learn the endgame, then you know what positions to steer for in the middlegame (endgames that are more favorable for you). If you learn this, then you can begin to play openings to steer you into middlegames you like - which you can steer into endgames you like

Easier said than done though, if you can reach the level of chess where you can steer openings into middlegames and middlegames into endgame effectively... then you are probably a titled player with a chess.com rating well over 2000 and 99% (no exaggeration) of chess players never get that far.

We don't need to become chess grandmaster and dedicate our entire lives to chess just to become "decent" enough to beat most of our friends at chess though

I'd start by researching (or messaging me questions on) basic "theoretical endgames" and basic "checkmates." This will help a lot, but not always does a beginner reach an endgame, but everyone begins in the opening of chess, so reading this opening principles hyperlink in the meantime is a good start in the correct direction. 

See ya around chess.com

Dear MagicGamerBoy,

I am a certified, full-time chess coach and International Master, so I have seen it and tried it all.
There are so many ways to get better and I know it can be overwhelming.
You can learn from free videos on youtube, there are books at your disposal that can all help, but they are not tailored to your needs.

One of the most important things you can do is to analyze your games! You must learn from your mistakes! That is a priority. You can't really move on to a new, different topic and learn new ideas if you still make the same mistakes over and over again!

This is where a chess coach comes into the picture. A good coach can show you how to study,  what to study, and give you the material YOU need. Naturally, it takes time to use everything in practice, but you will succeed if you are relentless and persistent!
You should learn the main principles in every area of the game (opening, middlegame, endgame).  Don't focus on only one part! You should improve your tactical vision as well as it is part of all areas!  
This how I built my training program for my students. We discuss more than one topic during a lesson so it's always interesting and they can improve constantly. I give homework too and the right tools to make practicing enjoyable and effective!
Don't worry about your rating and the ups and downs! Just keep on playing and practicing!

I hope this helps.  I wish you good games and 100+ extra ratings