How do I keep always on on at night for a clock?

Here is how you can use that feature on your iPhone 14 Pro or iPhone 14 Pro Max:--> Use Always-On display with your iPhone 14 Pro or iPhone 14 Pro Max (read section "Always-On display goes dark when you don't need it" too).

If you meant something different, your can submit your request to Apple directly, using this form:--> Apple – Product Feedback - iPhone

Regards

Giulio

If you use the sleep focus, you cannot keep on your always on screen