Space and time are not the same thing, they are facets of spacetime. We are only able to traverse space because we can properly perceive it, we do not have the ability to traverse time. I obviously understand the movie is fiction, it’s still a decent attempt at showing what it might be like to be able to truly perceive and traverse time. Our way to understand it (as depicted in Arrival) is the ability to actually see and experience the past and the future. You and I and no being we know about has the ability to see anything except the present.

As an example, the screen you are reading this on presents a 2d image. It does not have the ability to produce a 3d image (though we can make illusions that seem like it sometimes). That screen is constantly moving through 3d space (on spaceship Earth), but you still wouldn’t say that it’s presenting a 3d image because it doesn’t have the ability to directly interact with that space. Just like how we are moving through time but don’t have the ability to directly interact with that spacetime.