Really. I thought you have to open a blank Excel workbook to begin with.
Alan
Bill's suggestion above will work most of the time - for the vast majority of CSV files I would say.
You never need to open a blank file first - but sometimes it helps to use the import options, which means you have to have Excel open, albeit with nothing, not even a blank workbook, open in it. There is no issue if you *do* have something already open - it is not required though.
You can then do File - Open, change the 'type' to Text files (which includes CSV files), then open the CSV, and use the wizard to choose options appropriate to the CSV file, and your requirements.
If you can share a bit more about what your specific need is then we can provide more detailed and appropriate suggestions for your situation. Is this a one time need, or do you have hundreds of files to convert? Is there anything interesting about the input CSV files? Why do you want to convert them? Etc...
"how to convert csv to excel" doesn't give us a lot to go on, so you are getting some general suggestions based on that.