Excel Function that differentiates "male" from "female" names with 900+ names

What is your logic that you would use if you were to explain in simple English how you would want to do this. How would you distinguish between the Genders? Do you have a key in your spreadsheet? And then how would you distinguish these names: Kelly, Lee, Morgan, Carol, Shawn, etc. We need some more information here.

Make a seperated list with the names you have many times in your list.

Then you can use vlookup to fill the original data (in a adjecting column)

See my solution in #3.

with that many names, you are bound to have many duplicates. i would suggest you start by creating a list of unique names, seperate those into m/f, and then use vlookup() in your original table to find the m/f's