New to Apple....

AS a new Apple software user, with an iPad air2 I am finding it all quite confusing especially as my mail seem to have been hijacked or hacled, but. by whom? Apple or my internet server ORANGE or even MSoft, as used them on iPad 1st time last night.and today although just signed in to communities via looking at iCloud mail, the page sayes unauthorised access. But I am the only administrator! What's going on please Apple, have you got your own moderators locking people out?