remove alias of my Apple ID

If you mean you have an @icloud.com address, and because you were previously a member of Mobile Me an @me.com address (with the same text before the '@), and possibly an @mac.com address if you go back far enough: or if one of those two is your ID but you also have one or both of the others: you can't remove the alternative versions - they are in effect the same address.

If you are getting spammed at one of the addresses you could set up a Rule at the iCloud website to move all messages to that address to the trash. Go to the Mail page, click the cogwheel icon at bottom left, and choose 'Rules'.

That's what I'm talking about, assuming your Apple ID is an @icloud.com, @me.com or @mac.com address. whichever one of these is your ID, the others are referred to by Apple as 'aliases' and can't be removed

Do you mean 'email alias' - an additional address (not account) - which would have a different text before the @ from your ID address? You can remove this in the Mail page - click the cogwheel icon at bottom left, choose Preferences, select the 'Accounts' tab of the pane which opens, select your alias in the list there and click the '-' sign beneath the column.

If you don't mean any of this then I don't follownyou and would ask you to explain in detail what you mean (don't post your email address in the process).

See if anything here helps.

iCloud - Create or change email aliases.