Syncing calendars from Mac to iPhone 11 Max Pro

My appointments appear in Mac but do not appear on my iPhone.

I have sync both devices thru Icloud. Have open calendar in phone and have the iCloud calendar same as in Mac.

There is no way to add calendar thru settings >Passwords & Security>Apps using Apple ID

Do I have to use a USB cable to sync ? if so one time or every time I add some appts in the Mac?

Thanks