my instance not showing Application Navigator,Content frame, Banner fame

Hi ServiceNow Community,

I am currently using a Personal Developer Instance (PDI) in ServiceNow, and the interface has changed to the Next Experience UI. I no longer see the familiar sections like Application Navigator, Content Frame, and Banner Pane.

Could anyone guide me on how to switch back to the classic UI with those features?
Any step-by-step instructions would be appreciated.

Thank you!