apple id is associated with a deleted email address

I had to change my email address and my Apple ID is totally confused. I was able to put in an active email address for messages but it is not sending anything to that. (i.e. on iPhone, Settings/iCloud at the top it says "Account not verified" "Check your email at ..old address.. for instructions to verify this account.") When I try to set up iCloud on my iPhone almost everything is grayed out. I am constantly asked to log in to iCloud.

I can download apps from the App Store but I cannot use iCloud and cannot make any changes to it in Settings. I cannot back up anything in iCloud so am afraid to upgrade the operating system.

I previously shut off iCloud because using it cost me $20/month in data transmission for no cost to use iCloud, but now have unlimited data.

I have no idea what caused any of the problems.