Star Citizen will be huge! This applies not only to space, but also to the planets that can be traversed.
In a new video, it was shown how a character from Star Citizen wanders around one of the planets. The planets will be procedurally generated, not handcrafted. This allows the developers to quickly create the many planets. Special locations, such as stations, will then be added. However, these are intended to be handcrafted.
Just land and get out
In the game, the process will be such that you fly your spaceship to a planet, seamlessly penetrate its atmosphere, and then land somewhere. Finally, you get out of the ship and wander on foot across the landscape.
However, you should not expect to discover detailed landscapes with many NPCs on every planet. The majority will likely remain more or less “empty,” thus providing areas for PvP battles or smuggler hideouts. So, for most planets, players will likely be responsible for the “content.” However, that does not mean that the developers will not also take care of content on the planets as much as possible.

You can already get out on space stations or simply float in space. However, the developers of Star Citizen are still working on making all of this feel more natural and introducing better animations.
Additionally, weightlessness plays a role on the ships themselves. If the generator for artificial gravity is hit during a fight, players will float around the ship, making it harder for them to perform their tasks. Or you can disable gravity on a prison station to free a friend.
When Star Citizen will be released is still uncertain. However, due to all the features, a release is not to be expected before 2017.