You can do that by changing the data type. Look at these screenshots, and let me know if you have additional questions or need clarification. Depending on what you're working with, Table From Array and HTML table from collection may both be available, and both are similar in purpose.
Then, grab your array by the asterisk (*) and pull it onto the text merge designer.
When you drop the variable on the canvas, this popup is presented, and you can choose columns to include:
Once you click OK, leave "Table From Array" selected as the type, click the variable you put onto the canvas, and the bottom-left panel will provide configuration options for the table.
