How to pronounce this? Ich habe keine Ahnung! Bitte, help! I have the same doubt of pronouncing that word.
How would you like it explained?
Half of the sounds simply don't exist in English, so comparing them to English words won't help.
One standardised way of representing pronunciation across languages is the International Phonetic Alphabet (IPA), which is what I used.
You could try listening to pronunciations on Forvo: https://forvo.com/word/r%C3%B6cke/#de (though the one by fw3493af sound a little odd to me).
If you know how German is pronounced, then the pronunciation of Röcke is obvious; if you don't, then I'm not sure how to explain it, especially if I don't know what languages besides English you do speak.
(For example, would it help if I said that the German short ö as in Röcke is like the French eu as in neuf while the German long ö is like the French eu as in deux? Or that the German r at the beginning of a word is similar to Arabic ghayn or French r?)
How to know the difference between plural and singular Madchen?
In this sentence, you can tell that it's plural because of the article die.
das Mädchen = the girl; die Mädchen = the girls.
I thought the audio was saying "Jacke" instead of "Röcke". Hard to differentiate :(
Your sentence is (nearly) correct (the noun Mädchen has to be capitalised) but it means something different -- it means "The girls are wearing the skirts".
That is, your sentence talks about certain specific skirts that the listener knows about, perhaps because we had just been discussing them, while Duo's sentence is not about any skirts in particular -- just skirts in general.