Hi James,
Enter this formula in cell C2: IF(A2="test",B2,"")
Translating to English, the formula says:
"If cell A2 contains (only) the word "test", get the contents of cell B2 and copy those contents to 'this cell', otherwise, place a null string ("") in 'this cell'.
A null string, also known as 'the empty string', is a text value with length zero, and displays as an empty cell.
You can learn more about the IF function (and the related IFS function) in the Function Browser built into Numbers. The Browser opens when you type an = in a cell, telling Numbers to treat what follows as a Formula. typing IF in the search box in the browser will bring up the IF article, which includes a sample formula showing the syntax of the IF function, A description, and at least one example of how to use it in a spreadsheet.
Regards,
Barry