The PROPER function in Excel allows us to convert text to the right case in a quick way.
You would have to use the Proper function with the cell address. Let's say cell A2 has the text with improper case such as, "PART of THE WORLD." When you put a formula : = Proper(A2), you would get the text in the proper case: "Part Of The World."
Note that you wouldn't get closer case correction than this with inbuilt functions.