Hello @Jan257,
The link is of the form https://airbnb.com/rooms/yyyyyyy where yyyyyy is your listing number.
Using the link seen by clicking "Edit listing" will give a link to the page where you yourself can edit your listing. It won't work for others as it will point to a page to which only you have access.
Probably the quickest way to get the public link is to just type "https://airbnb.com/rooms/" in whatever application you're using and then add the listing number. Click on "Host", then on "Listing". then place the mouse pointer over your listing photo. Your listing number will then appear in the text at the bottom left of the browser window. Use just the number from this link.
You can also share your listing on other sites and get its public link as follows.
1) click on yout profile photo
2) select "Edit profile"
3) click on "View profile"
4) click on your listing photo
5) cllick on "Share" in the top right corner of the photo.
You'll then see options for sharing on Facebook, Twitter, by email and one to copy the link. If you copy it you can then paste it in whatever application you choose.
Steve.