Hello

If I recall right, you don't have to enter any code. Your invited friend enters your code and it's done.

When you are the recruiter, you will gain 5 gold chocobo feathers, and a ballroom etiquette with the fist pump emote. You also gain 5 more gold feathers each time you invite a new friend (up to 5).
Depending on your friend's subscription time, you will get more rewards, like a Friendship Circlet or a chocobo mount for two.

Your -invited- friend will get the friendship circle too (it boosts exp rewards), the emote and 10 silver chocobo feathers.

So all that to say by inviting a friend, you will get rewards and they will too. They're just different rewards, the recruiter gaining better ones to be honest lol

More info here : https://na.finalfantasyxiv.com/lodes...riend_recruit/

Have a nice day