Hello @Anna Schröder ,
Could you please share more details on your requirement? Do you want to share Calendar with other similar products like Google application? If that so, You have to use tools like Appy Pie. Please watch a YouTube video explaining the same here: https://www.youtube.com/watch?v=BPp-NsLPlVI
Please mark as "Accept the answer" if the above steps helps you. Others with similar issues can also follow the solution as per your suggestion
Regards,
Manu