How to erase my iPhone XR?

To delete your iPhone and restore it to factory settings, do the following:

First. If you want to make a backup, then you need to make it before deleting everything. If you do not want to save anything then you can just move on. Here's how to make an iCloud Backup:

https://support.apple.com/en-us/HT203977

Once your Backup is done:

Sign out of Find My iPhone, go to:

Settings -> Apple ID (Your Name) -> Find My

Sign out of Find My iPhone

Then, take a step back.

Settings -> Apple ID (Your Name)

At the bottom, select Sign Out.

Now your iPhone is no longer associated with your Apple ID and you are ready to restore the phone to factory settings. Go to:

Settings -> General -> Reset -> select Erase All Content and Settings, enter your code and your iPhone will now be restored to the factory settings. All content will be deleted.

When the phone displays the "Hello" screen, you are done.