Hello,
I see you may have a disabled device or forgotten device passcode for your iPhone 6+. If you see a waiting period you can try again after the timer ends. You can also use a computer to reset your device, as described in this article --> If you forgot your iPhone passcode - Apple Support .
Read the support article for full information. You can also watch the 5 min. 16 sec. Apple video "How to restore your iPhone if you forgot your passcode" at https://www.youtube.com/watch/7s8-zLG9ySQ
Thise will result in erasing the iPhone. You can, however, restore it from a backup as described in this support article --> Restore your iPhone, iPad, or iPod touch from a backup - Apple Support Some items will restore automatically once you make sure you are signed into iCloud (if you were using iCloud to sync these services).
Here are resources if you are prompted for your username and password and have forgotten them:
If you forgot your Apple ID email address or phone number - Apple Support Note that typically this is an email address you use.
If you forgot your Apple ID password - Apple Support
If you do not have a computer, use the link Find Locations to find an Apple service location, or ask a friend if you can use theirs. This could be either a Mac, or a PC with iTunes.