OntarioCanuck - 1/15/2019 07:27

If you are serious about learning about what we know about evolution and especially how dinosaurs evolved here are a couple links for you to read.

https://nhm.org/site/research-collections/dinosaur-institute/dinosaurs/birds-late-evolution-dinosaurs
Recently, fossils of early birds and their most immediate predecessors have been collected at an unprecedented rate from Mesozoic-aged rocks worldwide. This wealth of new fossils has settled the century-old controversy of the origin of birds. Today, we can safely declare that birds evolved from a group of dinosaurs known as maniraptoran theropods-generally small meat-eating dinosaurs that include Velociraptor of Jurassic Park fame.


https://www.quantamagazine.org/how-birds-evolved-from-dinosaurs-20150602/

But it has become increasingly clear that the story of how dinosaurs begat birds is much more subtle. Discoveries have shown that bird-specific features like feathers began to emerge long before the evolution of birds, indicating that birds simply adapted a number of pre-existing features to a new use. And recent research suggests that a few simple changes — among them the adoption of a more babylike skull shape into adulthood — likely played essential roles in the final push to bird-hood. Not only are birds much smaller than their dinosaur ancestors, they closely resemble dinosaur embryos. Adaptations such as these may have paved the way for modern birds’ distinguishing features, namely their ability to fly and their remarkably agile beaks. The work demonstrates how huge evolutionary changes can result from a series of small evolutionary steps.

Lots more out there if you keep looking and learning.