How to Add Table Header?

In Zoho Writer, I created a table.

I want to add a header to the table. Meaning, I want to make the top row as the header.

When I type the text on the top row, it gets wrapped and doesn't cross over to the next column.

I have removed the cell's right border. Still, it gets wrapped.

I have attached the sample doc.I have attached the sample doc.

How would I have a header without getting the text wrapped?