I kind of get lost when I start reading through the help files, I was hoping someone could offer some insight?

So right now, the way my project is set up is that when you are close enough to merchants, their shop opens up in the player's statpanel, where they can shop, like mystic journey.

I'd like to take that idea and have the merchant's statpanel instead pop-up in their own independent info panel instead, that seems like it would be more intuitive.

I am currently trying to figure out how to set the mob's inventory to the "MerchantInfo" infopanel. Would I use winset()? I am not having much luck doing so.
You can't have multiple info panels. BYOND only supports the one.
Oh. Thanks.
You may not be able to use more than one info panel but you can use a grid to load the merchant contents instead. At least if that's what you're trying to do.
Could do something like
mob/var/list/inventory = new
mob/var/list/shop_inventory // Set this to the list of items in the shop

for(var/object in inventory)
if(shop_inventory && statpanel("Shop))
for(var/object in shop_inventory)