I didn't choose to have a wifi/Bluetooth module when I bought the LCD, but I need to use it recently, so I want to buy one and solder it myself, how do I choose?
You need the details from the manufacturer of the board, or at least a board with it fitted so you can copy the components off of it. You need to know what the chip is, and what all the missing component values are. The board might also need reprogramming, as it might be disabled when not fitted.