Hello,

I saw the screenshot you attached.

You need to edit the product categories element that you used to display the categories on the homepage by editing the homepage. Then you can find the options for the layout for the element.

Screenshot for Clarification: https://ibb.co/xYywQhr

If you are still unable to set it then provide with admin panel login details of the website to check it myself and help you out accordingly.

Best Regards.