They are making vehicles to go to mars with and they haven't gone yet. And it is said that they want to camp there and bring people and even have a space camp.
Are they building on mars or do they have a camp there?
No and No!
Part of the problem is the Mars One scam. You can see there are many posts here specifically containing the search term
"Mars One": https://space.stackexchange.com/search?q=%22mars+one%22 and despite all of the hype, we can take the word of Canadian astronaut, space musician and public outreach figure Chris Hadfield who said it as clearly as it can be said:
Mars One was a scam.
The reality is that there are serious concerns about the physical and mental health issues associated with a six month trip in a tin can to Mars, and a huge! amount of money and time necessary to bring supplies infrastructure to Mars before humans could survive there. See answers to How might the experience of a trip to Mars differ in comfort and heath impact from a stint on the ISS?
There are no camps on Mars and there are no serious plans to do it in the near Future. It may happen one day, but it's not just around the corner.