https://account.proton.me/u/30/mail/referral does not provide any assurance about my data shared with the referred user, for example i do not want referred user know my name or email address. If email is revealed to a referred user, then I would like to be able to customize which email address of mine they would see.

I can not find any privacy details of the referral program at https://proton.me/support/referral-program

Btw. https://lumo.proton.me thinks that my primary email address is shared with the referred user. Ask:
"When using Proton referral program, is my email address shared with the referred user? Can i customize which of my email address is provided to the referred user? Short answer please."