HI and welcome.
I would wait to start your car, sitting is really hard on it. I would get the bentley manual for the SC and learn about Porsches before doing too much. Wayne's book is also good, and there's plenty of information here.
I would drop the engine first so you can check everything and clean iit up (also makes getting to the plugs easy). You can read the procedure on dropping the engine here. Definitely change the fuel, filter and accumulator, put in a pop-off valve in the airbox.
Leaks are common on the lower valve covers, most people replace the stock ones with the turbo valve covers (and new gaskets), the oil return lines would probably need to be replaced as the seals are probably cracked from sitting (another common source of leaks)
There is an oil additive you can get that luminates under black light (I think it's black?) so you can see where the oil is leaking from. I would also add techron to the gas (when you replace it) to clean out the system, but your oil will need to be changed again after a tank of gas has been used.
These are just the starting points, good luck and read, and ask alot of questions (after doing a search in this forum for the ansers
)
Good luck