Some very basic Chess questions from a total noob

So I’ve played a fair bit of chess, but never with any sort of strategy or training. I’m at a 820 right now.

I’d like to start to think more strategically and just play better overall.

A question I’ve always had regarding openings is how circumstantial they are. I feel like whenever I look up an opening, it’s predicated on like 2-4 moves the opponent has to make in order for that opening to take place. How does one use named openings routinely if the odds of the opponent doing the necessary moves are so low?

Another question I’ve had is what aspects of the game to focus on if the aim you’ve put for yourself is to simply be able to consistently beat a total beginner. Is picking a couple white and black openings and practicing them a good move?

Thanks in advance a lot!

@1

"I’m at a 820 right now."++ Then your main concern should be to always check your intended move is no blunder before uou play it.
Hang no pieces, hang no pawns. When your opponent hangs a piece or a pawn, take it.

"regarding openings is how circumstantial they are."
++ Do not worry about openings. Just develop pieces into play and play for the center.
You will not win or lose because of the opening, but because of tactical mistakes.

"2-4 moves the opponent has to make in order for that opening to take place."
++ Frequently played sequences got names for easy reference. Nobody must play that way.

"How does one use named openings" ++ You cannot. You depend on the moves of your opponent. Do not worry about openings. Develop pieces into play and play for the center.

"what aspects of the game to focus on" ++ Blunder prevention, then tactics, then endgames.

"Is picking a couple white and black openings and practicing them a good move?"
++ Yes, in descending order: a defence against 1 e4, a defence against 1 d4, a white opening.
Recommended are 1 e4 e5 and 1 d4 d5 as black and 1 e4 as white.

Hi, Khapungin, you need to understand opening and do not just memorize moves. There are some ways to learn chess openings, one of them is understand the logic behind every move. I am writing the article on opening for beginners. , i just written the article on fried liver attack, you can check and see if its easy to learn or difficult to learn.

Improving Your Chess - Resources for Beginners and Beyond...

https://www.chess.com/blog/RussBell/improving-your-chess-resources-for-beginners-and-beyond

https://www.chess.com/blog/RussBell

You should play simple, easy to pick up openings and focus on opening fundamentals like deploying the pieces, controlling the center, defending your pieces before learning complex openings and lines. 

(My answers in bold above for clarity)

1st: How to win with one pawn in endgame I mentioned earlier

2nd: hour long video but goes through how to analyze your own games with a computer for learning and teaching yourself

3rd: my most recent video which is certainly beginner-compatible, once castled why pawn moves in front of your King weaken it and usually should be avoided

I got this,...

I'd say blunder checking is the biggest area for improvement in my game as suggested above. Openings kind of fall into place but regularly get taken apart from not seeing what the opponent is doing and adjusting the setup accordingly. If I could see all the candidate moves each time I'd never be surprised but that is above my pay grade currently.

the above answers ... play to control the center and develop .. are right, but to answer your question..

if your opponent does not follow the expected responses in an opening -- and sometimes there are a great many of these, the variations of that opening, for example Sicilian has a bunch like alapin or dragon or whatever versions -- they have likely done something that gives you an advantage.  The kicker here is that the advantage may be on par with a computer evaluation that you are  0.003 pawns ahead: something a GM may see but not easy to spot or exploit.   Or it could be game changing and easy to spot, like maybe they played the losing side of the fools mate.  

Following the advice given, you may indeed be giving up some tiny advantage that would get you punished by a 2500+ ranked player.  For a long time, though, if you play to the center/develop and follow general opening tips given above, you will be just fine.   If you stumble into a trap or a lost game within 10 moves, study your specific games and figure out what you are doing wrong.