Problem: How to have a N3 send a response

New and different project time here. I need a smattering of help in writing C# code for one of my N3s to accept an input on say GPIO2 and then wait a few moments and then send it back out on GPIO3. Please note those were chosen at random and do not reflect the final needs of the program. See, in my N1 days I was able to write a doozy of a program that simply activated four of the GPIO locations, not including zero and one, then caused the connected four place NAND gate to go active and then a solid-state relay activated causing an electromechanical counter to advance. Then naturally the four of them would change state and so would the NAND gate, and the counter would release,. This would cycle four times.
In this case it would be the along the lines of this pseudocode:
GPIO goes into input mode and accepts an input from a bounce eliminator
Program stores data in Variable A
GPIO goes into output mode and passes Variable A to connected input of NAND gate buffer
[program repeats, that is it goes to starter point.
And that’s the <EXPLETIVE DELETED!) problem. I know how to code it in of all things BASIC and the dialect spoken by the Parallax BASIC Stamp devices, but not C# as understood by the Netduino family here.

Doctor Who8 Gregg
“That takes me back!” The Fourth Doctor.

Ignore this one group. I just realized that it won’t work.