[K0P]

Ive seen that the extension for the folders in windows 10 is .ink but ive not experimented to create a file with extension as ".ink" because i didn't had time,i have a question,will it make a folder if we make a file like this?

[Misiur]

As name suggests it's called "file extension". Folder is not a file, therefore it doesn't have an extension (even if you call it "folder.txt" it won't have an extension, just name "folder.txt"). *.lnk is a shortcut file, not a real folder.