Just got new iPhone 6 I backed up the iPhone 5 to iCloud from the phone. Now i don't know how to retrieve the files from iCloud to the new iPhone 6
You should've had an option to restore from iCloud when you were first setting up the phone. You can erase the entire phone by going to General reset reset everything reset all settings, and then start the initial set up again. Make sure you use the same Apple ID and iCloud account.