The good news is there are no answers there either ... the writers and the directors don’t agree on what happened either.

“Avengers: Endgame’ Writers Disagree With Directors About How the Film’s Timeline Works“
https://www.slashfilm.com/endgame-time-travel-writers/

Right. If you go back in time and change something, you're on a new path and the "old" future you came from exists and carries on unabated. Which is why it makes sense that Cap went back into the past, but his living with Peggy was a different timeline/reality, and somehow he skipped back into ours to give the shield back. This also means there were probably two Captain Americas in that timeline, but he probably rescued Bucky early and sniffed out Hydra.

There's no main timeline for Steve to put the stones back. All of those pasts where they slightly altered things became different timelines. Putting the stones back just meant trying to minimize the changes, and not screw them completely over (like had they not returned the time stone that reality was going to be screwed over by not having a sorcerer supreme with that power).

OK, let’s try it this way ...

You are looking at time within the human construct of time. You are thinking in terms of seconds, minutes, hours, days, weeks, months, and — in particular — years. These are Earth-bound concepts based on the rotation of a planet and it’s orbit around the sun.

Time, in this galactic conceit, is the movement through reality. Time travel is not altering the linear movement through “Earth time” (years, months, etc.), but moving through the multitude of realities/possibilities (“galactic time”) that exist. By moving into the “past” it becomes your “future” (actually, your “present”) because you can ONLY continue moving forward, just on an alternate “timeline” (or, more accurately, an alternate “reality line”). You cannot go backwards at all.

Here is an illustration:

Your timeline is ABCDEFGHIJKLMNOPQRSTUVWXYZ where each letter represents an event in your life.

There is an alternate reality, uh “time”, where something is different ... maybe you did/didn’t get married. That line goes ABCDEF1G1H1J1 and so on, where at event F your life diverged.

Back in “your world” somewhere around event N, you decide you want to see what would have been. So you travel to the alternate world for F1, G1, and H1 before returning back “home”. So you now see your timeline as ABCDEFGHIJKLMNF1G1H1OPQRSTUVWXYZ. However, you traveling back to F1G1H1 is actually O. O was always you “traveling back”. You can’t change your past or your future (because events that come after the chosen point are already in your past). You can move to an alternate reality.

And now I’ve gone cross eyed.

(And yes, I used the term “home” very deliberately to describe your original “time” line. I think “Far From Home” may have a much different meaning than we previously suspected. Especially with Mysterio being a entity that can alter “reality”.)

Holy shit. I can read this anymore.

They will clear up their logic in future movies. Till then, we are just guessing the writers intentions.

Now that time travel exists in the MCU, future movies can revolve around it. It could easily be the entire basis for Ant Man 3.

Saw this today after a week of turning off social media to avoid spoilers. My dad couldn’t wait to see it, otherwise I usually wait 3-4 weeks to watch blockbusters.

Packed theater at 945am and I say I got lucky because everyone was respectful and quiet! I was amazed haha

As for the movie, I thought it was good, emotional, and since I LOVE time travel plots, I was super pumped with the storyline. I avoid trailers and commercials, so I had no idea time travel was involved.

And of course the end battle was epic.

The camera panning through the funeral, with the superb music was excellent.

excellent movie experience!

but still to this day, Winter Soldier movie is still my favorite. More realistic action in that movie, which I prefer over fantasy action.