Human landing on Mars

[Xiao li]

Launch a lander carrying robots and rocket parts. The robot will assemble the rocket and use Martian resources to provide energy. It will be launched into a transfer orbit to meet with the manned lander launched from Earth and land on Mars. After the lander takes off, it will dock with the rocket and return to Earth.

 

[rustythebailiff]

Agreed. A lot of questions can be answered before sending a human crew. Can plants grow in the Martian regolith? Is there water and can it be obtained in sufficient quantities? Can we build habitats using regolith? And many others.
It's a shame the NERVA project was cancelled. We could have had nuclear engines in the 1980s and been travelling to Mars decades ago.

 

[Rob77]

Launch a lander carrying robots and rocket parts. The robot will assemble the rocket and use Martian resources to provide energy. It will be launched into a transfer orbit to meet with the manned lander launched from Earth and land on Mars. After the lander takes off, it will dock with the rocket and return to Earth.

While this sounds like an ideal plan, realistically our technology in robotics is still too far away to do all those tasks you mentioned. We would be able to land humans a lot sooner before we can achieve all that. IMHO - the MARS mission will most likely play out just like the movie "the Martian", where several unmanned Starships are sent ahead with fuel, resources etc.