Depends on what you plan on doing to stop from saving them on iCloud.
What exactly are you planning on doing?
You can choose to save your notes to the "On My iPad" location or to an email account location that's been added to the device and appears under "Folders" in the Notes App.
Anything currently saved in iCloud would remain there unless you manually move them to one of the other locations in "Folders".
If you decide to turn off Notes in iCloud in Settings->Account(top of settings)->iCloud->Notes, then you will be asked if you are sure. If you answer yes, all notes saved in iCloud will be deleted from your device, but will remain untouched in iCloud.
If you are planning on doing something else, you need to explain what that is.