Work out heart rate zones

When I look at more details for average heart rate for a workout, there are heart rate zones 1 to 5. The rates that the zones are set for are not useful for me as a 60-year-old. Zone one is < 125. A moderate cardio rate for me is 112 - 135. I would like to have zone one top out at 80, zone two 96-111 and so on. My point is zones will vary by individual as well as by age. It depends on what advice you’re following. Can I set those ranges somewhere? I have entered my date of birth. This is about the fitness app with data input from my Apple Watch. So it is an app, but I do not see it offers that as a topic.