How do I add more rows and columns to a table that's already placed down in InDesign?

https://helpx.adobe.com/indesign/using/selecting-editing-tables.html

A great new invention is here, called Google! 😉

Fourth way: use the Tables panel. The top row items are the number of rows at the left and number of columns on the right.

Click in the table and choose Table Setup. In that dialog you can change the number of rows and columns.

Hi Acha1,

if your cursor hovers over the bottom or top edge of a cell and the double-arrow is showing, simply hold the Alt key and drag down the cursor: That would add rows to the table. If your cursor hovers over the left or right edge of a table cell, hold the Alt key and drag to the right to add columns.

Regards,
Uwe Laubender

( ACP )

Click into the table and go to Table>Insert>Row.