I'm sure it's already been asked and I'm really sorry to ask again if so!.. But.. I have an EA access version of the demo so not pre-ordered. Will I have the ability to give 3 friends codes or is that strictly for pre-order versions?
Yup you will get 3 codes. Check this link for the token after you load the game once.
https://www.ea.com/games/anthem/anthem-demos/friend-referral