How do I set continuous backspace deletion on iPad with keyboard?

I want to delete an entire line of text - some of my former iPads would backspace easily erasing as it went

my newest one with keyboard doesn't do that - I/m sure its a setting - anyone know how to set it to backspace delete?

[Re-Titled by Moderator]

Original Title: How do i set my retrurn key or any key to be a continous backspace ?