Hello Kctong
In Switzerland, for regional travel, we do have zone-based tickets. Although you purchase a point-to-point ticket, it is converted into a ticket containing zones. And, a return ticket converts into a zone-based day pass.
Zone-based tickets allow unlimited travel within the ticket’s validity, and zones indicated on your ticket. And this, no matter on which service: train, tram, bus, boat. A ticket to Stein am Rhein will also include zone 110, which stands for the city of Zurich. Consequently, you can also use it in the city of Zurich before or after visiting Rhine Falls or Stein am Rhein.
The cost of a so called Z-Pass Ostwind-ZVV Day Pass is CHF 58, full fare.
Enter: Zürich HB - Stein am Rhein via Schaffhausen, return, 1/1 tarif.
Now, alternatively, you could purchase a Saver Day Pass, if available from CHF 52. You could purchase the Saver Day Pass that is valid for the entire country. The downside of the Saver Day Pass, the cost is raising the nearer the travel date; thus you have to purchase it early, and it can’t be cancelled.
https://www.sbb.ch/en/tickets-offers/tickets/day-passes/saver-day-pass.html?
The Z-Pass Ostwind-ZVV Day Pass you can purchase on the day of departure, the cost is always the same. The latter leaves you the flexibility on the decision if you would like to take the excursion or not.

With the Z-Pass Ostwind-ZVV Day Pass, you can travel in all these zones:
https://www.zpass.ch/dam/zpass/Zonenpl%c3%a4ne/2023/2728_ZPass_322x282_OSTWIND_23_low.pdf
Please let us know if you have got more questions.
Kind regards,
Roland