Below are your parts
Parts for Frigidaire FEF336ECE Range - AppliancePartsPros.com
I am not sure where your part numbers came from as I come up with different ones. See Items 20 and 20 A in the Backguard Parts section.
The one I find is 7 button and the one you cite is a 10 button.
Check out the overlays.
Also if you click on a part's picture a new page will open with more info on that part.
I would unplug the the unit and remove the back just to be sure that a wire has not burned off.
If OK then the likely cause is the control board is toast.
I am assuming that the stove top elements work OK.
Am also assuming that the unit stays in pre-heat and does not show that the oven is ready.
Some overlays are stuck to the control board/clock and often also have to be replaced.
I cannot tell if this applies to this unit from the pictures.
The part's people may know this.