I've got the idea of werden, würden, wurden etc. However, my German teacher pronounces würden like wurden, which I believe is wrong as I have listened to German singers say it differently. How is it correctly pronounced?
"ü" and "u" are pronounced differently. You need to find a German-speaker (or a recording) to hear the difference. Here's a link to some examples (but not very good quality) https://de.forvo.com/search/w%c3%bcrden/
https://www.dict.cc/?s=w%C3%BCrden Just klick at the speaker button and you can hear how words sound in german and english.