Warning: This post contains MAJOR SPOILERS for Captain Marvel and its end credits scene.
"Where's Fury?" That's one great question, but we have a few others after seeing Captain Marvel's first end credits scene. While we always expected a connection to Avengers: Endgame, we were not prepared for that gasp-inducing moment when (a longer-haired) Carol Danvers answered Nick Fury's final page, especially because of when it happens in the MCU timeline.
In the scene, Steve Rogers still has his long hair and luxurious beard (RIP) from Infinity War, which have been totally absent from the Endgame teasers, indicating it didn't take very long for Carol Danvers to come back to Earth after the Snap. Also, the urgency in that scene that we see in Steve, Natasha Romanoff, Bruce Banner, and James Rhodes strongly points to them having found Fury's pager shortly after Thanos snapped, and that Captain Marvel arrived soon after that.
While Carol's arrival among the Avengers is an incredible moment on its own, it raises a whole bunch of new questions for us to obsess over.
What happens in the immediate aftermath of the Snap?
The final shot of the Avengers in Infinity War shows the survivors silently grieving in the forest of Wakanda, totally crestfallen. In the Captain Marvel post-credits scene, they are hard at work on something. How quickly did they gather themselves and spring into action? The planet certainly needed them, since half of every government on Earth has vanished, so the faster they regrouped the better for everyone.
Who found Fury's pager and when?
The remaining Avengers were all in Wakanda when Fury turned to dust, so who actually located his pager and brought it to the team? Was it one of them, or some other survivor who had the means to help them? How long after the Snap did that take place? The fact it was found at all and given to the right people is good news, since it means there is still some level of infrastructure, even in the face of global mayhem.
How soon after Infinity War does Captain Marvel show up on Earth?
It's clear it was soon after, but was it a couple of days or a couple of weeks? We at least know that it was long enough that the Avengers hooked the pager up to an outside power source.
Either way, the arrival of a secret super-powered hero who can crisscross galaxies in a short time is a huge boon for the devastated Avengers, either in the form of a major reinforcement, some much-needed hope, or just to have access to someone who is more familiar with the rest of the universe and can go do intergalactic reconnaissance or missions with them. Carol Danvers could be exactly what Earth's mightiest heroes need, and the faster she gets there the better.
Where was Captain Marvel between films and what was she doing?
We know she said she was going to end the Kree war and mend the universe, but how long did that take? Was she still doing that during the Snappening, or had she moved on to other missions? Did her travels through the cosmos the last 24 years bring her into contact with any of the Infinity Stones, Thanos, or any other powerful beings who might be of use now? What did she learn during the time she was away? And did Fury ever page her back to Earth previously?
Where is Captain Marvel between the end-credits scene and the time jump (where we see a clean-shaven Steve Rogers)?
With Carol Danvers arriving shortly after the Snap, but Endgame looking like it will have a gap of at least a few years before the Avengers put their major plan into action, where is Captain Marvel during that time? Is she on Earth with them (and possibly the "missing" Avenger from the last teaser)? Is she flying through the universe looking for the Mad Titan or any information that will be helpful? Is she recruiting powerful allies (maybe some old Skrull friends)? And if she did leave Earth again, when will she come back? Is she out looking for Tony Stark?
How will Captain Marvel’s abilities help reverse the Snap?
Carol Danvers gained her incredible powers when she blew up Wendy Lawson's lightspeed engine, which exploded in a wave of energy. It gave her nearly unparalleled abilities in the MCU, including the ability to shoot photon blasts with her hands and fly through space. But the source of those powers might be more relevant than the powers themselves. Lawson made her drive from the Tesseract, which contained the Space Stone. We know that gives Captain Marvel an intimate connection with the Infinity Stone, because Wanda Maximoff also gained her powers from the Mind Stone (which was trapped in Loki's scepter). That was how Scarlet Witch was able to destroy it at the end of Infinity War, before Thanos used the Time Stone to undo it.
Captain Marvel's connection to the Space Stone could help her locate it, and prevent Thanos from getting it in the past before the Snap. She might also help the Avengers collect the Stones themselves, but it won't be enough for them to just undo the Snap, they'll need to destroy the Stones so it can never happen again.
There's no question Carol Danvers will be important to saving the universe. The question is whether she's the best hope.