How to place an order in open market?

Hello! I am new here,So can someone please tell me how to place an order in open market.
(I want to buy smartphones from catfishsales.)

The Open Market lists products that are available for immediate purchase. You click on a listing and buy it.

Note that the listing has to match your selected business, so if you have a Retail Automotive business you can only buy Automobiles (you will not see a BUY button otherwise).

To place an order, you have to use the DIRECT SALE option to find a supplier.