This 29 August 2018 video says about itself:
Theropod Dinosaur Size Comparison
Theropods first appeared during the Triassic period, about 230 million years ago, and gradually diverged into many different lineages. At some time during the Jurassic period, or perhaps earlier, one of the lineages gave rise to the first birds. Theropod dinosaurs survived until the end of the Cretaceous period, about 65 million years ago, when all the remaining non-avian dinosaurs became extinct, although of course birds (which technically are a type of Theropod dinosaur) survive to the present day.