How to sync iPhone calendar with desktop

Hi Padsfan,

Welcome to the Apple Community, where some of us do our best to help each other.

Wondering which operating system you have on your desktop.

Apple support have articles online to help you sync your calendars.

Please choose from the links (below) one that corresponds with your desktop's operating system.

Sync contacts and calendars between your Mac and iPhone or iPad

https://support.apple.com/en-au/guide/mac-help/mchlf24d4e49/mac

Or

Sync iphone calendar with my outlook calendar on windows

Discussion thread:

https://discussions.apple.com/thread/252866299

Or,

more generally:

Sync iPhone with your computer (using iCloud, or not)

https://support.apple.com/en-au/guide/iphone/iph875319a3a/ios

Sync content between your Mac and iPhone or iPad

https://support.apple.com/en-au/guide/mac-help/mchlde9a31f1/mac

Hope one of these methods works for you :)