"make duplicates real" does No longer exist in Blender 2.93?
There are alternative solutions to make duplicates to Single objects?
That depends on how you created your duplicates.
I believe Blender automatically converts old dupliverts into new instancing.
If you created the duplicates by creating an array, you apply the array modifier, then in edit mode select and use P to separate the parts by selection. If each object is a single mesh, you can select all and separate by loose parts.
If you created the duplicates by using Duplicate Linked then you separate the duplicate by making it single user, most easily done through the Object menu: