Uses the countif function in excel to find duplicate cells except first one.
The formula is =COUNTIF(A$1:A1,A1)>1
If the countif function returns a number greater than one then it means the value is duplicate and the value of the cell will be set to true.
If you want to highlight the cells that contain the duplicate values you can use conditional formatting and apply the same formula.
Go to Home tab and click on Conditional Formatting and then to select New Rule.
Select Use a formula to determine which cells to format
Add the formula after adjusting it to your needs such as cell and row to start.
Select the format options you need click ok and apply it to the cells you want to the condition to be applied.
Here I chose to highlight with yellow all the duplicate cells except the first one. You can then filter the rows based on the cell colour.