Like what @vvaidya posted you can execute key combinations that access the Excel menus; by pressing Alt you will see letters appear above the menu options, so maybe Alt+a+m is an option to Remove Duplicates. (for example, Select Range then TypeInto “[k(alt)]am” or Send Hotkey)
Are you wanting to find the unique values in a row or in a column? The solutions might be different. But, you can look into LINQ solutions that are the fastest and more reliable, I think:
You can also convert the table to a string with Output Data Table, then use .Replace if you only want to replace certain words. Probably not the ideal method for your goal of getting rid of duplicates.