basically he is telling him to go read the documentation on docker, which i understand you cant help people by giving them the answer they need to figure it out for themselves, but a better solution would have probably guide him to find the solution at least that way other who come here looking for an answer will have an easier time.
What happens then if you simply can't figure it out for yourself? You come to this forum and ask for help.
Basically calls you and idiot and you thank you him,