Why do I always have to enter a verification code when accessing iCloud .

If you’re signing in with a web browser at www.icloud.com you can choose to “trust this browser” and you won’t be prompted often for a code. You must have cookies enabled for the web browser.

Nope, you likely have two factor authentication turned on which requires a verification code (https://support.apple.com/en-us/HT204974). could you give more information. are you signing into the same place each time? if so, you might be able to not require a code for that specific browser or device. i would need a bit more information.