The programming on this is trivial. Reading the switch transitions is less than a dozen lines of code. Incrementing a counter each time the switch is pressed is one statement.
The switch statement with three cases, with three function calls is another dozen lines of code.
What you want to do in the functions (LEDs on full, LEDs strobing (whatever that means), and LEDs alternating) is trivial, as far as the LEDs go.
What exactly "The speaker is to go off on each setting with similar behavior." means is unclear. I don't believe I've ever heard a speaker strobe. Nor, do I understand what "on at full brightness" means to a speaker.
Some clarification of the requirements is in order.
Now, about the hardware. Is the hardware known to function, or is it a pile of parts that may or may not be complete? Some clarification of the hardware status is in order.
If you are supplying the hardware, vs. a list of part numbers that you hope can be brought together in a usable manner, it is certainly easier if you don't have to ship the parts half way around the world.
Some clarification of your location is in order.
I"m looking for quick turnaround on this...Please contact me through email as soon as possible.
Why do I get the impression that you've waited until the last minute, and are now panicking?