Hello @Gunhild1 ,
Welcome to the Community Center!
I had a quick look on my Airbnb account and was able to find the home safety section where you can select whether you have a smoke detector or not.
Please try the following steps:
From the homepage, click on ‘Host’ > Listings > Click on the listing you want to edit > Scroll down until you see ‘Amenities’ and then click on edit > Scroll down until you ‘Home safety’ and click on edit > You should now be able to see a safety checklist.
The checklist should look like this 
Let me know if you were able to find the checklist :-).
Quincy