Hi! here's a YouTube video with the right pronunciación: https://youtu.be/ftwfTsNu7mc

Pronounce "prej-" to rhyme with "edge." This word has the stress. Pronounce the "u" as the indefinite vowel, the schwa, ə. If you're not sure what that is, try not to pronounce any vowel at all, just try to pronounce the "j" and the "d" one right after the other. Pronounce the "-dice" like "diss." Overall, "PREDGE-a-diss." Or listen to a recording in an online dictionary like ahdictionary.com (US) https://ahdictionary.com/application/resources/wavs/P0523100.wav or oxforddictionaries.com (UK) https://en.oxforddictionaries.com/definition/prejudice and click on the speaker icon