Ok so whenever I download the toma343b.zip from library, and I set things up, everything seems to be fine but however the only issue is that the sound isn't working. Did I install the sound correctly or do I need to do something else? It tells me to copy the soundai from the default A320 but the only thing missing is the sound. Here is the download link: https://library.avsim.net/search.php?SearchTerm=toma343b.zip&CatID=root

If you open the sound folder from that download you will find only a .cfg that aliases another aircraft's sound.  Most of these aliases don't work.  Just copy your sound folder from the default A321 and paste it into your new aircraft folder.