Not much to go on here, but this might be West of Eden (1984) by Harry Harrison. The protagonist is a human(ish) who was raised by the dinosaurs who had recently discovered and begun to colonize what we'd think of as the new world. As a young adult, he is "rescued" by another group of humans, and has to adjust to living among his own kind, then to act as an intermediary between the humans and the dinosaur folk.
There was also a sequel that retconned around the fact that humans (in our world) descended from African apes, so shouldn't have occurred in a world where the dinosaurs never relinquished the Old World.