Is the landing gear controlled by the pilot or is it automatic?
The landing gear system is operated by the pilots. The extension and retraction, depend on the action from the pilot monitoring, on 2 pilots operation.
The pilot has a lever on their panel, on which they select the extension (down) and/or retraction (up).
Some aircraft has a system to avoid extending them on high speed, to avoid some damage, and on the ground, avoiding retracting, for obvious reasons.
There are lights, green and red, indicating their position.