Complex sentence: Juan and Chauk are able to arrive to Mexicali where they get help from a group of immigrant traffickers to cross the border between Mexico and United States, but they are left on their own in the desert, where Chauk is killed by an immigrant hunter.
Split into simpler sentences: Juan and Chauk arrive in Mexicali, where they get help from a group of immigrant traffickers to cross the border between Mexico and United States. The traffickers take the boys across the border, but leave the two on their own in the desert, where Chauk is killed by an immigrant hunter.