iCloud email addresses

My Apple ID is not an iCloud email address. My son had an iPhone and used my Apple ID but also created two iCloud emails years ago. This hasn’t really been a problem for me until recently. I am unable to delete those two iCloud accounts from my account. There isn’t an option to delete them. I created an iCloud email alias for myself but that didn’t let me delete the other two. I have searched Apple’s site, tried everything in the iCloud email settings. My iPhone tells me I am not allowed to delete those two email accounts. I’m not sure at this point if I’m just stuck with them or what. Has anyone else ever had this happen? Thank you!