Create a list
To create a new list, select + New List in your list menu. This will create an untitled list that you can rename.
Share a list
To share a list, open the sharing menu by selecting the sharing icon in the top right of any list you've created.
Once the sharing menu opens, select Create Invitation Link > Copy Link, then paste the sharing link in your favorite email or messenger app to send to your collaborators.
To turn off the sharing link or limit sharing to the list's current members, select the sharing icon to open the sharing menu. Select Manage access > Limit access to current members and no additional members will be able to join the list.
You can also select Stop Sharing to turn off the sharing link. Once you stop sharing, current list members will no longer have access and your list will be private again.
Microsoft To Do supports list sharing for the following scenarios:
Sharing between personal Microsoft accounts.
Sharing between accounts within the same place of work or education.