Excel validation for a drop down list

Hello,

I am trying to achieve this :

I have name range CATEGORY 1
Another name range with CATEGORY 2


I have a cell drop down with CATEGORY1 ,
Now , if i select CATEGORY 1 in another cell, it has to give a drop down list of the CATEGORY2 based on my selection.

Please help me, on how to do this as I am not an expert in excel.

Thank you for your help.