Open the Notes app
Tap the Back arrow until you see the Folders list
Tap Recently Deleted
Find the deleted note
Tap Edit
Select the note
Tap Move To
Choose the folder where you want to restore it
If you do not see it in Recently Deleted, check iCloud Notes
Go to Settings
Tap your Apple ID
Tap iCloud
Make sure Notes is turned on
Open Notes and check the iCloud folder
Restore from an iCloud backup if available
Go to Settings
Tap General
Tap Transfer or Reset iPhone
Tap Erase All Content and Settings
Set up the iPhone
Choose Restore from iCloud Backup
Select a backup that contains the note
Restore from a computer backup if available
Connect iPhone to a Mac or PC
Open Finder or iTunes
Select your iPhone
Choose Restore Backup
Select a backup that contains the note
Check other email accounts linked to Notes
Go to Settings
Tap Mail
Tap Accounts
Open each account with Notes enabled
Check the Notes app folders
If the note was permanently deleted, contact Apple Support