Yes. All organisms, both living and extinct, are related. In the tree of life, every branch represents a species and every fork separating one species from another represents the common ancestor shared by these species.
Scientists are able to sequence DNA and fossils and find descendants joining their ancestors.DNA analyses show that although humans share far more genetic material with our fellow primates, we still have more than 200 genes in common with bacteria. You share genes with yeast, flies, worms, mice and with the cotton fibers in the shirt you’re wearing.