on the libre spreadsheet I wish to insert columns and rows in the body of an existing project. How do I go about doing this/

I realize this a a very basic question and am somewhat embarrassed asking it. On an Open Office Document, there is a panel for inserting columns or rows. I can not locate anything resembling this command.
Any help you can give me will be much appreciated.
Rob

What’s wrong with right mouse click on a column (e.g,. E) and selecting Insert Columns Before or Insert Columns After – or – right mouse click on a row (e.g,. 10) and selecting Insert Rows Above or Insert Rows Below ?

PS: If you select # columns and Right click -> Insert .. then # columns will be inserted. Same for rows- That’s why the context menu shows the plural columns and rows.