An email will be sent to whatever account is connected to your Epic Games account. it can take 10-30 minutes for the email to arrive so you might have to be patient. You can pick which discord account to give the nitro to, however if your Discord account has EVER had nitro, you will not be able to redeem it. you will need to put in card information to redeem it SO REMEMBER TO CANCEL IT IN 3 MONTHS IF YOU DO NOT WANT TO CONTINUE YOUR SUBSCRIPTION