iCal (as it was), Google Calendars x3, kids' calendars, etc--I couldn't find a way to keep things simple, but I had read reviews (reddit, elsewhere) of people recommending BusyCal for MacOS and iOS. I'm on the bandwagon now. It has helped me organize, streamline, simplify my calendars--centralizing things and being able to spend less time reorganizing things. I think there are a few minor wishes (can't send emails without MacOS "Mail" opening despite this not being my OS default app which is Gmail on Chrome, missing native Google Workspace features like seeing Google Calendar resources or invitees schedules, more granular control of tasks prioritization) but these don't stop me from giving this a 5 over a 4 (4.5 would've been my choice if it was possible). I installed this on my phone and feel the same. I still might use Google for some situations (like above) but I usually start from BusyCal and take over elsewhere for anything that needs native features. Hopefully, the devs behind this will find wasy to tap in to those features or maybe make their own solution. I'm a fan and think if you are struggling with multiple calendars, this will be your solution.