• https://www.php.net/manual/es/function.array-push.php

   $pila = array("naranja", "plátano");
   array_push($pila, "manzana", "arándano");
   print_r($pila);

Otra forma:

   $canasta = ["naranja","plátano"]
 
   $columns[] = "manzana";
   $columns[] = "arándano";