Why "Crewed" instead of the more common "Manned"? Although "Manned" could mean someone of the species "Mankind" we have decided to avoid any possible hint of sexism, and show that any of the first crews could be a female, we will use the word "Crewed".
Who will be the first to go? Who knows, That will be decided later. It will be whoever is the most qualified, and has shown the most commitment to the project.
The rest of the crews? Same answer.
All of the first generation Astronaut Explorers will have to go through certain training. Not all of the training that will be required is known yet, but what categories are known will be described here. (Discussion of specifics and category types should take place on the discussion page.) Beyond being in good physical, mental and emotional condition, with no disqualifying conditions, (TBD) They will need to have exceptional problem solving skills in exotic conditions with limited resources, be able to be able to tolerate standing (supported) at 4g, not be subject to motion sickness, not be subject to adverse reactions to inconsistent or exotic lighting, (flicker vertigo for example) be able to tolerate extended periods (up to a week,) of micro-gravity, able to tolerate both enclosed spaces, and vastly open spaces, and be able to tolerate falling from extreme distances.
Crew members and invited explorers will need to be trained in;
Lunar geology (What is the right word for that? When someone who knows better enters it, It should be turned to a link)