Thanks for stopping by the Apple Support Communities. From your post, I understand that your iPhone 7 Plus seems to have remove all your content, and after signing into iCloud again, you don't see anything being restored. I'm happy to help!
First, make sure you're signed into iCloud with the correct Apple ID under Settings > [your name] > iCloud. I would also recommend signing into iCloud.com with that Apple ID, and checking the various apps (like Contacts, Photos, Calendar, etc) to see if your information appears there. If it does, go back to Settings > [your name] > iCloud on your phone, and make sure those options are enabled.
In addition, if your data in an iCloud backup, try restoring it. You can do the same if you have a backup in iTunes. Steps for restoring from both iCloud and iTunes can be found here: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support .
Have a great day.