Mercury is the closest planet to the sun. Being small in size as compared to Earth it is a very hot planet.
The surprising fact about the planet is that even being closer to Sun it has poles that are rich in ice( possibly because some regions on mercury never receive sunlight due to its orbit and orientation ).
The maximum temperature near the equator can reach 430°C certainly not in favour of human life while at poles it can reach as low as 80K (-190°C) . Mean temperatures can be about 70°C at equator and -70°C at poles roughly. Hence none of these seem to be close to Sustainable temperatures for human.
Hence landing on the planet may require a high insulated spacesuit that can resist heat at proximity to the Sun. Such suits need to be made of high melting metals or alloys. However they may make them heavy and uncomfortable. Suppose these suits are made and you get a chance to spend 24 hours on mercury.
Here’s how your day would be like-
Mercury day is about 60 Earth days. So its better to land on that side of planet not facing the sun so that your 24hrs are fully spent in dark and you are free from Sun heat and light.
Mercury has almost no atmosphere. So you’d need a sufficient oxygen supply(using oxygen cylinders ).
You’ll also need protection from solar winds of sun. Mercury is very close to sun and all the harmful materials ejected from sun at high speed ie the solar winds have high intensity at the distance of mercury. Mercury thankfully has a magnetosphere but still it faces strong solar winds. Hence you need a protection from it too.
Once you land there you’ll be not lucky enough to see Sun from close as you are on its opposite face as landing on side facing the sun may cause further difficulties throughout your day and spoik the fun. However you can have a close glimpse of Sun when your Rocket is just set to land on the planet.
You can see Venus closely (though mercury and venus are closer to one Another most of the time than Earth and Venus, Earth makes closest approach to Venus.) You can’t view any of the Mercury’s moon as it has none. You can see the Earth.
If you are an astronomer you can verify certain facts about Earth. Like it’s size. You can watch the Moon from a different angle(if its not hidden behind Earth).
However landing on Mercury is not much fun and interesting due to it’s harsh weather, proximity to Sun. You can say it is an enemy to life.
Besides the mission can become very very costly.
Spending a day on Earth at a beautiful location may prove to be better and feasible than on Mercury where you have no chances to be alive- you dont know if you’ll be blown away by some tornado or swallowed by volcanic blasts..
Possibly because of this MAN has not landed on MERCURY