WHAT OPENINGS TO LEARN FIRST
Learn openings in roughly the same order they were popularized historically. So as white, learn Double King Pawn Openings (1.e4 e5) first, then Semi-Open, Double Queen Pawn Openings(1.d4 d5), Flank, and lastly Modern/Hyper-Modern openings. As black ,the situation is more challenging as basic defenses need to be learned for all the above. The Modern and various closed openings require good pawn play to be effective so they are de facto more difficult than Double King pawn and semi-closed games; beginning players have a full plate with just basic tactics, endgames, and checkmates.
Don't.....
Don't start trying to learn and comprehend a bunch of openings below 1200-1400 level. It's pointless... Pick a few moves that are good development moves example 1e4, 2.Nf3 and 3.Bc4 etc and get a good grasp of the tactical mechanics. Learn to adjust those moves around what your opponent is playing. Memorize a few tactical traps that involve those moves (BUT!!!!! NEVER ever chase the trap... if it happens it happens)
Then once you get to say the 1200 elo level... Don't attempt to construct a repertoire around Openings or Defense not related pawn structure wise. You will just spin your wheels trying to memorize lines and never grasp the concepts and ideas. Once your opponent plays something out of "Book" you become lost and loose.
Openings are an OXYMORON.... they are overrated, yet underrated at the same time. I truly believe 95% of the known Openings and Defenses can be played with regularity regardless of the ELO.
Pick a pawn structure that you like, that you know you will see often... (don't attempt to learn an Opening or Defense that you see 1 game out of 20... that is a waste of time. ) If you pick something, as long as it adheres to decent opening principles it doesn't matter. The goal is to learn how the pawn structure works in conjunction with the pieces. What the plans are, what the opponent can do to counter you idea. It's about NOT memorizing lines
With all openings or defenses ... sooner or later, an opponent will play an equalizing line... NOT understanding the pawn structure and the themes it contains leaves you guessing after that point. The more I play the more I've learned ... Blunders aside ..... Chess is about having a plan, and enacting that plan... plans get checked, counter plans get put into play,... they get checked... back and forth.
It's all about the pawn structure and how the pieces work together in conjunction with that pawn structure. IMO... At first it's best to build a repertoire with overlapping themes and pawn structures. If you are new to chess.... or If your time is limited, or you are old like me... IMO this is the way to go.
Ignore #6. What he says does have merit, but not for a novice player. At a beginning level, one needs to understand the fundamental principles of the various components of chess, but only the most fundamental. Simple tactics, 1-ply,and 3-ply,is where most of a beginning players efforts should go, emphasis on simple, You DO need an opening or else you'll lose outright early, or at best, have a losing position by move 10. Pawn structure chess is almost meaningless below Class C play, games will be decided by one and three-ply tactical shots, not by gradual evaluation shifts due to solid pawn play, i.e. big evaluation squiggles vs small ones. In fact find a double king pawn gambit that you like and adopt it as your white opening, make dropping pawns a virtue while being forced to learn all the chess opening and middle game principles out of necessity.Cut the Gordian Knot,just play 1.e4 e5 openings see if you prefer the gambit or non-gambit ones and adopt one.
Learn openings in roughly the same order they were popularized historically.
I'm a big fan of doing things in exactly that order... in real-life temporal order.
Study Morphy's games before going on to those of Steinitz, Tarrasch or Nimzovich.
Study open combinational play before studying closed positional play.
Learn the white side of 1.e4 e5 first, select only one to play as white from Italian, Scotch and Ruy Lopez. Then play this selected opening as black against the same opening. This will be the main game you will end up playing. As black select an opening for 1.d4 and play that exclusively as black, this will be your next strongest opening. You will face other openings less often as black. As white you will need to have openings against the next most common responses to 1.e4 this will take longer to learn. You will see the Petrov as the irregular 1.e4 e5 variant, most common non symetrical responses are Scandinavian, French, Sicilian, Caro-Kann, Pirc. If you start getting good winning results as white in all the common response lines that is when you can choose to play something else. Note, if you play 1.d4 as your main opening for white try to limit yourself until you have solid results and understanding against the most common responses, then you can choose to leaen 1.e4. It has been a common recommendation to learn 1.e4 first.
Note. Of course as black you will have to face in 1.e4 e5 the Italian, Scotch, Ruy Lopez, The Vienna, Centre Game and Kings Gambit. But at least you should be stronger in your most focused opening when playing 1.e4 e5.
I think it is best to learn while you are playing instead of focusing on the book alot. Each game is different. I reviewed my games alot just to make sense of what I might have missed. I am also still learning