I have been watering it (not too much) and have made sure that it’s in a good spot to get sunlight! I don’t know what else to do :( any help/suggestions would be very appreciated
What kind of pot it is in? Looks like there could be a possibility of water collecting at the bottom?
Looks like only one branch is problematic so far. I think, there is no root problem, but some kind of canker infection above the ground.
Hard to tell exactly whats going on, possibly root rot. But i would repot into a well draining soil mix (bonsai soil) and into a pot with drainage holes. That way you can water without worrying about over watering, nor water collecting in the bottom.