A free falling body doesn’t experience gravity but is moving relative to a stationary observer. This observer experiences gravity. – check.
An accelerating body experiences “gravity” and a stationary body observed by the accelerating body appears to be in motion. – check.
There’s a Veritasium video that covers this: [Why Gravity is NOT a Force](https://youtu.be/XRr1kaXKBsU).
Here’s where it gets a bit mind-bendy though. If the surface of the earth is stationary, why is it pushing up on our feet like the floor of an accelerating rocket would? Is it because although it is stationary relative to our space, it *is* moving through TIME?
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It’s pretty complicated yes.
Spacetime is curved by gravity. In order to be stationary in curved spacetime you’d have to be accelerating in a universe that appears flat.
>Is it because although it is stationary relative to our space, it *is* moving through TIME?
Kind of yeah, but the important part is that it’s moving through curved spacetime. If you’re in space far away from earth you’re also moving through time without accelerating.
You’re always moving at c, if you’re stationary you’re moving at c in the time direction, if you move quickly through space you move slower through time. If you are within curved spacetime then a part of your movement through time becomes a movement through space because space and time are interlinked
The details are hard to ELI5 and involve a lot of heavy math.
Maybe I can find some “general relativity exlained in simple terms” but I guess they’ll also just state those facts and can’t explain the why. The why is simply “because that’s the only way it can both be true that movement is always relative and the speed of light is a universal limit”. There is no other way to make the math work out with both of these staying true
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