Looking for a way to change a calendar without login

Hey, I’d like to make a calendar “publically” available in my LAN and everybody should be able to change entries. Ideally the URL would be something simple like http://cal/

What I have tried so far is to just share a calendar and open that URL, but then one is not able to edit it.
What I also tried is setting up a local WebDAV Client (tried InfCloud and AgenDAV) with hardwiring them to a technical NC user. But I ust can’t get them to work with Nextcloud.

Does anybody have a working connection from a web based CalDAV client to nextcloud or another idea to reach my goal?

thanks in advance!