The first step in using iCloud is to access the iCloud Web page and then sign in using the Apple ID. Follow the onscreen instructions to verify identity by feeding in the code sent to a trusted device.
The requirement of the second verification applies in case there was a selection of two-step verification during the initial setup. To avoid being asked to verify the identity each time during sign on, use the Remember This Browser option that is available. Use a supported Windows or Mac Web browser.
Using the Apple ID to set up iCloud on the iOS device or Mac allows the use of all the iCloud apps. The
iCloud apps include Mail, Contacts, Find My iPhone, Pages, Numbers, Keynote, Notes, Reminders, Photos,
iCloud Drive and Settings. Once signed in, use any of the apps.
After signing into iCloud, switch to another app by clicking the name of the current app at the top of the iCloud window, and then click the other app. If the account has access only to the iCloud web-only features, then only Pages, Numbers, Keynote and Settings are accessible.
To sign out from iCloud when the Keep Me Signed In feature is active, go to the Settings option and click the Data and security option. Next, click the Sign-out Everywhere option and click the Sign Out Of All Browsers option, or directly sign out by quitting the browser app.