Nephew 6yr old has some green puss coming out of his eye last nite was very red now a little red an he says it hurts what could it be? Wht can I d?

Infection. A colored discharge usually means bacterial infection, this seems to be in the lacrimal drainage area. One has to worry about an infection of the lacrimal sac. The only way to be sure is to have him seen by an eye care professional.
Needs antibiotics. Please don't delay! He needs antibiotic eye drops. Sometimes bad conjunctivitis like this can get out of hand and cause corneal scars!