I have some research that it needs a good space suit to protect you from heat and cold but I need more so, what does planet mercury need to sustain life for humans? what could we as humans do to have the things that mercury need to sustain life?
A scifi trope I've now seen more than once (KSR's Mars trilogy and later works, also Stross' Saturn's Children) is the idea of a habitat on rails that drives around Mercury remaining on the terminator (eg. the night/day boundary). This involves the train being propelled by thermal expansion of the rails caused by sunrise to ensure that the system can operate in an entirely passive and unpowered way, though other means of power would also work (but have different mode of failure).
You'd want plenty of emergency escape boltholes underground where you could be safe from the sun in the event of having to abandon the train. Honestly, cool-factor aside, deep underground is probably the most sensible place to live, and deep underground on Mercury isn't going to be vastly different from being deep underground on any other rocky world, gravity and mineral availability differences aside. Once you're down there, the business of building hollow living spaces, sealing and pressurising them and filling them with stuff you want like air and farms and what have you, isn't going to be uniquely mercurial.
Actually, the most senisble thing to do would be to stay in orbit, probably. Stay on the dark side so your safe from solar radiation. Or just not visit the planet at all, and leave it to the machines. There'll be more pleasant and hospitable places to go, by the time humanity is capable of colonising Mercury.
$\begingroup$ mercurial: (of a person) subject to sudden or unpredictable changes of mood or mind. $\endgroup$– L.Dutch ♦Nov 18, 2019 at 19:44
$\begingroup$ mercurian: Adjective. of or relating to Mercury (the planet). $\endgroup$ Nov 19, 2019 at 3:30
Mercury’s axial tilt is only a few degrees so the ideal place to build a base would be at one of the poles. With the sun effectively circling the horizon a modest sized crater would provide areas of perpetual sunlight on the rim, areas of perpetual shade at the bottom and areas where sunlight and shade alternated every 50-60 days or so around the crater walls.
In addition polar craters are believed to contain some water ice
So they would be an absolute go to place for a Mercurian base providing ample heating and cooling, plentiful potential for energy production, water, oxygen and rocket fuel. The crustal rocks are also high in aluminium and silicates that could be used for construction work.
The major problem is getting there at 13 km/s deltaV from low Earth orbit to the surface of Mercury.
It depends what you mean by sustain life. If you're happy for people to live in sealed environments then this is a feasible, if challenging engineering challenge. Living outside of a sealed environment would be so difficult to be impossible in my opinion.
Mercury is very close to the sun, and spins slowly. This means it is both very very warm (the side currently facing the sun), and then very cold (the side facing away) - varying between -173 Celsius and 427 Celsius. The polar regions are merely a frosty -93 Celsius but at least that is constant due to no major axis tilt.
Thus a Mercury habitat would either need to be able to endure extreme cold(a polar habitat), extreme heat and extreme cold (an equator habitat), or through a different engineering problem neither.
Mercury "rotates" at about 10.8 km/h at the equator. Thus if a mobile habitat were to move at 10.8 km/h along the equator it would remain in the same degree of shadow relative to the Sun. There is some hypothetical point near the terminator of Mercury (ie the point of sunset/sunrise) that is neither too hot or too cold, and would require less insulation / cooling. This is still a very difficult challenge, but another option to consider for a Mercury habitat.
As mentioned in other answers, living underground is the most likely and plausible means of survival on Mercury.
However, living in a cave is pretty depressing, and fails to take advantage of some of the features of the environment. I would suggest that the colonists would dig a huge shaft at each pole, and cap it with a transparent, radiation prof cover (perhaps a cap of transparent material like diamond with 5 m of water between the plates). A mirror on the surface or in orbit reflects some of the available sunlight through the clear end cap and into the shaft.
The Colonists live in a city which essentially lines the shaft. Here they are protected from solar radiation and the thermal extremes, but have access to abundant sunlight for gardening and living in a pleasant, semi tropical environment. Trees and plants can line the walls in planter boxes, providing both natural colour and providing part pf the ecosystem for the colony. Ice and other elements needed for the life support system can be sent sunwards via mass driver or using a solar sail to kill the orbital velocity around the sun, and these facilities can be located in orbit or on the equator, providing a high level of safety (a missed cargo can crash on the surface without affecting the city). Similarly, mining operations and mass drivers to send metals to the outer solar system are also located on the equator, well away from the dwelling areas. Temporary or semi permanent "camps" can be set up around the machinery for work crews to monitor and repair them, but this will be like living at a mine site or an offshore oil rig, not permanent accommodations.
So living on Mercury is possible, and there are many possible options that future colonists could take.