This picture of a landing gear assembly on a lab test rig shows how big it is; the foot pad's diameter is easily 2.5-3 feet.
The lunar module is the part of the manned spacecraft that will actually touch down on the moon's surface. When used, the upper half of the module blasts back up into orbit to rendezvous with the orbiting command module.
Landing gear is a critical for a successful lunar mission. It needs to be able to brace the rest of the lander, as well as actively adjust to uneven terrain by manipulating its computer-controlled struts assemblies. Like the rest of the module, the landing gear needs to be shielded against thermal changes as well as be robust enough to handle the surface impact. (For context, the Apollo lunar module had a terminal speed of 7 feet per second). Since the landing gear is the only part of the module that will make actual contact with the lunar terrain, it may also contain instruments in the landing pads to gather scientific data on lunar soil.
From available pictures, the deployed landing gear appears to be about 11-13 feet high with a diameter of 32-40 feet. That should be enough to encase the lower stage of the lander, and total lander mass of 20-25 tons. It looks a lot like the Apollo lander, actually, with four collapsible assemblies, each terminating at a footpad.
Each assembly consists of a primary strut extending from the lunar lander's side, connected at its midpoint to two secondary struts running parallel to the ground. The secondary struts are connected to the lander itself by two truss side braces, with an X shaped deployment truss between the two side braces.
The new landing gear is likely to be used for a Chinese equivalent to the NASA Lunar Landing Research Vehicle. This system will train taikonauts on Earth to land and maneuver the landing module, in addition to validating the technology behind the landing gear.
The Chinese manned lunar mission will be launched by the super heavy Long March 9 rocket, which has a low earth orbit payload of 140 tons, and a 50-ton payload for trans-lunar injection. With the continued investment in the program, we can expect more systems from the Chinese manned lunar mission to show up in the next decade, as the new space race heats up.