If the car's in generally good shape, I would say just clean it up and get everything working properly, don't "restore" it - you will end up spending too much money, which then goes against the idea of a car to use every day!
As far as starting it up again, if it's been sitting for a long time I would first drain the fuel, flush through the system with a few litres of new and change the fuel filter: the old fuel will have "gone off", (absorbed water from the atmosphere, smells bad!) and there's also a good chance of sediment and stuff which will block up filters, jets etc.
I would also drain the oil and refill with new (and fit a new oil filter), and take the plugs out and run some oil into the bores, then turn the engine over by hand a few times; then hook up a battery and crank it over fast to clear the oil.
Clean and set the plugs (or buy new), clean the rotor arm and distributor cap contacts, and check for a spark (hold a plug against the head or block and turn over with the key, you should see a spark at the plug - don't shock yourself, hold the plug with insulated pliers or similar!
Make sure fuel is getting to the carbs; just slacken the fuel connection to each carb slightly and see if any fuel appears when cranking over on the key. Make sure it doen't leak onto anything that will start a fire!
If you have sparks and fuel, the engine should run; fit the plugs and tighten up the fuel lines, make sure there's enough fuel in the tank and the battery is good, and try to start it - it might take a few attempts but it should start.
When it starts, let it sit at a fast idle until it warms up; don't
rev it hard! While it's warming up check for water / oil / fuel / exhaust leaks, alternator charging and so on: when you're happy you can shut it down, and add some carburretor cleaner to the fuel; hpefully you won't need to strip the carbs.
It might not run very smoothly to begin with, and smoke & emissions will probably be poor to start with but they will improve with use if the engine's mechanically sound, so all you have to do now is service the brakes, check the lights, steering etc, and fix the gearbox! (exchange is ok as long as you get it from a good supplier) - as far as fuel consumption, it's directly linked to the position of the right foot, but Alfas are about fun, not economy..........
Hope this is of help,
Cheers and good luck!