backup
i have a new phone with data on it like pictures and so, and i back upped my old phone. if i restore my back up on my new phone from my old phone do i lose the data i have on my new phone?
iPhone 11 Pro, iOS 13
Yes. The first step of doing a restore is to erase the phone. The data from the backup replaces the data on the phone from before the backup. See: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support