How to delete multiple excel coloumn in c#

You can install Free Spire.XLS library via nuget, and then use the following code to delete columns with ease.

Workbook workbook = new Workbook();  
workbook.LoadFromFile(@"..\excel.xlsx");  
//get the first worksheet   
Worksheet sheet = workbook.Worksheets[0];  
  
for(int i = 10; i >= 1; i--)  
{  
    //delete the first 10 columns in the first sheet  
    sheet.DeleteColumn(i);  
}  
  
//save the excel file  
workbook.SaveToFile("sample.xlsx", ExcelVersion.Version2010);