You can use iCloud from anywhere by signing in to iCloud.com from a web browser recommended in the Apple Support article System requirements for iCloud.
Note: Not all iCloud features are available when you sign in to iCloud.com from a web browser on iPhone or iPad. To access more features, sign in to iCloud.com using a web browser on a Mac or Windows computer. See the Apple Support article Which iCloud.com features are available in the browser on your device.
Sign in to iCloud.com
Sign in to iCloud.com using two-step verification
Go to iCloud.com, then sign in with your Apple ID (the one you use with iCloud).
Follow the onscreen instructions to verify your identity by entering a code sent to a trusted device.
Note: During two-step verification on iCloud.com, you can choose to trust the browser so that you will not be asked to verify your identity the next time you sign in.
See the Apple Support article Two-step verification for Apple ID.
Switch to a different iCloud.com feature
At the top of the iCloud.com window, click the name of the feature you are currently using, then click another feature.
Sign out of iCloud.com
Do one of the following:
Sign out from the browser you are using now: click your name at the top of the iCloud.com window and choose Sign Out.
Sign out from every browser where you are currently signed in: go to Settings on iCloud.com, click Sign Out of All Browsers (in the Advanced section), then click Sign Out.