There's something that I want to discuss. What would be

A human can't face off against a panther any more than deinonychus, however how would they get into that situation? Our ancestors stayed in groups, slept in caves an surveyed their territory, hunting down dangerous predators.

It greatly depends. "Dinosaur" is a very broad term. On a chronological time line, the last dinosaurs are closer to humans than they are to the first dinosaurs. And the evolutionary conditions which led to the era of massive dinosaurs are just incompatible with the conditions which led to the birth of humans so it's mostly implausible for dinos and humans to coexist in the same habitat not because one would exterminate the other but because of different conditions. And unlike humans, the dinos wouldn't have made it through the ice ages. But in the end I guess it wouldn't be much worse than when early homos had to deal with mammoths and saber tigers.

In America, people who live in the country side often have to deal with bears, so they are often seen carrying revolvers and even shotguns just in case. So that would mean in an America with dinos they would be seen carrying heavier weapons, maybe grenade launchers and bazookas. Alaskan hunters would display, instead of grizzly bear heads and moose heads, T-rex heads on their homes. Dino meat would be an important part of human diet and niggers would enjoy buckets of fried dinosaurs they get from KFD (Kentucky Fried Dino). If you were to travel to France you'd see very expensive dino skin jackets and purses on sale by Louis Vitton and whatever other expensive name brands. History has had plenty of important catastrophes like the Versuvius eruption which fucked the Romans badly or the Fukushima tsunami, so dino swarms that completely destroy entire cities would make into these lists of important historical natural disasters. In Texas dino rodeos would be popular. Cowboys, knights and samurai would obviously ride velociraptors instead of horses and kings, because of their higher social hierarchy, would ride into battles mounted on a T-rex.