why CSV format changed and how to save utf8 from .xls

Hi,

This might be a wierd question,as the situation is for me, I faced an issue that I try to explain as deatailed as I can.

I exported csv file from woocommerce and it should consist of columns but it always comma separated. And former .csv that were comma separated open in columns. (it is after I got a new laptop with the same office version)

The question is why excel opens .csv in that way, like it switched the format?

Thank you.
Tamas