If you want to play multiple games for the same lottery for a particular drawing, you can do so using one order, rather than placing a bunch of separate orders.
Once you have selected the numbers you want, you can add the game to your cart by selecting the "Add" button. Then if you want to play more numbers you can select them and hit the "Add" button again. You can do this until you have all the games you want for that drawing. When you are ready to checkout you can select "Checkout" and pay for the games all at once.