the right answer should have been a Routine, but I just played with the UI and it doesn't have a duration or stop time. So getting it to stop at 8:30 is a challenge.
For the part about News, you have a choice of the News Flash Briefing, or set it to Music and then choose iHEartRadio or TuneIn to select an actual radio station if they have it.
I suspect the News Flash Briefing has a limited run time, so that's closer to what you wanted, and you should have configured News Flash briefing to come from sources you want (ex. NPR).
That much is doable. To get it precisely from a radio station for 30 minutes, oddly enough, it seems the 30 minute limit is the part that can't be done.