Hi, to use Modes, head over to Settings >> Modes and Routines >> Modes.
You can now select a mode from the given options, or create a custom mode as per your liking. Similarly, for Routines, just tap on the Routines tab at the bottom.
You can now tap on the compass icon at the top to search for suggested Routines. You can directly add them to your device, or customize them as per your liking.
Alternatively, you can create your own custom Routines as well by tapping on the plus icon at the top.