Nostalrius Begins - Quality wow vanilla realm (1.12)

I have a friend trying to add me and she told me to look at my pending tab on my friends pane. But, I do not have a pending tab. Is it because it is a Vanilla WoW? Or is something wrong on my end?

I made sure that I have Real ID enabled and it's been enabled since I created the account.

You don't have a pending tab. You can add whoever you want to your friends list, and get notified when they're online or not, regardless of them "accepting". It also works vice versa of course

Edit: There's no Real ID at this point of the game. Also that's a Blizzard-only feature, implemented in the later clients.

This version of the WoW client (1.12.1) is really primitive; there is no Real ID system; the Friends List can only add and show your friend's characters they play as. There is no pending, just Add and Delete. You are automatically notified as friends select their characters and enter the game world.

Either your friend has a different WoW client than you or they're just mistaking this old client for the newer ones like retail has.