Those look like AND gates to me and I guess that is what you need to have if you want to use PORTB.6 as enable.

Since you have GND to one side of the AND gate in your pricture.... GND AND anyvalue is still ZERO.

Try to connect one side to 5V or use the PIC connection and set the pin accordingly.

But if you use AND gates the output that is NOT enabled will be low. but if you want the opposite use a NAND.

/me