Does gloomy and look have the same vowel sound?

No, "gloomy" and "look" do not have the same vowel sound. In "gloomy," the vowel sound is /uː/, as in the Word "blue." In "look," the vowel sound is /ʊ/, which is a shorter and more closed sound. The two Words have different vowel sounds due to the pronunciation of the letters "oo" in each Word.