Most modern scientists agree that birds have not evolved from dinosaurs, they are dinosaurs. This is one of them, a common house sparrow.
Let me rephrase this for you – a common house sparrow is a dinosaur.
Birds are thus considered by most modern scientists to be dinosaurs and dinosaurs are, therefore, not extinct. Birds are classified by most paleontologists as belonging to the subgroup Maniraptora, which are coelurosaurs, which are theropods, which are saurischians, which are dinosaurs.