Do openings really affect the game

Depends how early you blunder, or walk into a difficult or unplayable position, or run out of ideas for middle and endgame from your prep. I play 1.e4 all the time, if I play 1.c4 on my next game I will be much worse as I can't recall plans for both sides and will stumble badly in the opening. The less you know what to do in those positions the more it shows under time pressure as well. I know general chess theory and habits but could still misplay a critical line. Then be trying to catch up for the rest of the game.

The opening you choose determines the pawn structure, the deployment of pieces, and which squares are vitally important to the resulting positions.

the stronger you are the more openings matter, but you still need a certain minimal level of excellence at the lowers stages or the game or you will simply always be playing inferior positions and rely on your opponents blunders to win.

This is also not only level centric but opening centric too. Some openings to be played with decent results at X level require differing degrees of memorization and understanding. It would take a lot more work for me to play say a grunfeld well than say, an old indian for example. Similarly, if you gonna reach 2000+ playing primarily the caro kahn, you bet you will probably need a more solid grasp of the endgame than other players since the main advantage there is the health of your structure.
there is really no good reason to neglect opening study. It is pound for pound some of the easiest points to make and studying openings unlike common myth actually does improve middlegame strategy somewhat. To play an opening well is basically to get the chance to play at an extremely high level for the first few moves. Practically a freebie in precision so to speak, why would you neglect that?

It has been observed, in track and field relay-races, that most events are decided by the last runner of the team; its clear the starting runner doesn't matter.

stick to running then, chess is not for you.

Well you need to master more than one aspects of the game in order to progress.

For beginners opening might not decide the game coz of obvious blunders that often decide the game. But as you are higher rated the obvious blunders come less frequent and most of the time needed to be forced.

Good opening knowledge is required to get yourself into somewhat advantageous or at least playable position. That way it's more likely your opponent would make a mistake before you would or he'd spend more time to handle the unpleasant position.

This is an obvious ...

thread.

Every Chess Game has an Opening!

BUT not every Chess Game has an Ending!

Think about it!

Sometimes game ends in opening, really..

Exactly - Sometimes, the game never reaches a middle or end game.

Sorry to offend people, but...

Weak players put WAY too much emphasis on openings. Openings are almost irrelevant below 1000 rating, and are of only minor importance below about 2000 rating.

Masters and Grandmasters need very detailed and in-depth opening knowledge. Patzers do not. What patzers need is board vision and situational awareness, so that they can notice when their Queen is being attacked. They need basic tactical skills, so that they can spot a two-move combination that wins a piece. They need at least a bare minimum of positional understanding, so that they can recognize a strong square or a weak Pawn when they see one.

So why do so many weak players focus (and waste!) so much of their time on studying opening lines and memorizing move lists? A few different reasons:

1. It's fashionable. All the cool kids study openings.
2. It's documented. You can find lots of already-prepared study materiel on openings.
3. It's a quick fix. It offers gain without pain. Or appears to. Improving your situational awareness takes a lot of work, and requires that you pay attention. Much easier to just memorize a series of moves, without understanding them.

How then should you learn? The HARD way. And the difference between the hard way and the easy way is that the hard way WORKS.

@blueemu, isn't it still common for titled players to blunder fairly quickly after theory ends? Gukesh played a really long piece of theory against Hikaru in Norway and made a positional blunder where he was in Zugswan for the rest of the game. Sadly you still need the skeleton of a sequence of plans to play well in general and if you are following a known opening having the correct plan sequence helps to not hang your pieces as you look at those plans before selecting candidate moves. Gukesh is world champion in classical, memorized a computer opening saw it was close to equal and didn't know that it was positionally lost because the evaluation could not see over the horizon and there was not sufficient counterplay to draw on from the plan. So the opening does effect the game. Yes low Elo blunders more, but on their best day it helps with the building blocks of understanding to have sequences of plans to play in an opening, middle and endgame projection. They dont need all openings, but the ones they play the most will help.

If these "sequences of plans" were gained FOR FREE, then of course it would help.

ANY additional knowledge will help, if it is gained for free, giving up nothing in return.

But the knowledge isn't being gained for free. A player who spends a third of his time studying opening move sequences will fall 33% behind other players in more general things like tactics, model checkmate patterns, endgame play, typical central Pawn formations and their effects on planning in the middle game...

With my elo I'm not sure I should be writing about this... but it's from the perspective of a club player...

I don't think I necessarily study opening par say, but rather I think I study pawn formations. I took up the triangle pawn formation. i.e. pawns at either d4, c3, e3 or d5, c6, e3.... Once I did that... I started learning how to attack with the pawn formation... e.g as White pawn to f4 or pawn to c4 etc, Then I took on openings and defense that had those pawn formations. At my level... I think it's been a benefit looking at openings this way. When I'm a known theoretical position that is equal, I understand the pawn formations enough to formulate a plan and not flounder.

I agree with Blueemu. Low rated players spend too much time trying to memorize opening sequences. Why? They think that is what higher rated players have done. What they don’t realize is that it is the understanding of the moves that makes a player stronger.

The top players in the world are also the top Fischer960 players. Nothing memorized. But they understand general principles—opening, positional, endgame—that apply regardless of the opening or starting position.

Yeah right.....if you follow an educated path...in todays world that is forgotten.

Everything is chatgpt. Learning the game aka game theory? What is that?

Now, even chatgpt is lame. Gamification is in...for the masses. Talent is a whole different path...as usual. No different than any other sport.