Wow, looks like a pretty good barn find - I bet you will be able to get a lot done yourself, including getting it started and running the first time. Everyone has an opinion, here is mine:
Most parts you can find at https://centerlinealfa.com
or Vick Autosports, The Premier Fiat and Alfa Parts Source
, and more obscure stuff can be found at https://classicalfa.com/
Buy this: https://www.themotorbookstore.com/al...er-manual.html
(shop around for a cheap price)
Buy this: https://www.wesingram.com/pricesheet.htm#book
Remove the battery and just get a new one. If it doesn't hold a charge later on down the line, you'll know it's not that, and I'll sell you my spare alternator.
Hose down that engine bay - @AlfistiSA
is spot on for engine bay cleaning procedure
Swap out the plugs - NGK BP7ES
New cap and rotor - make sure you figure out exactly what is needed, not sure if you have a MarelliPlex or..?
Fuel filters - replace the rear one for sure, whether you think it needs one or not.
Replace the engine oil, oil filter, SPICA filter - do all this at once, I like Castrol GTX 20W50, and the oil filter they sell at https://centerlinealfa.com
Coolant - There is a well documented process to refilling the coolant so that you don't get air bubbles trapped in the system, be sure to follow this.
Transmission and diff oil - Use Redline 75W90 NS (NS is the important identifier) in the transmission, and Redline 75W90 in the diff.
Clean/replace the air filter - K&N makes a good replacement
New fan belt
Inspect braking system & replace brake fluid
Inspect /replace clutch cylinder fluid
Check the SPICA - @Roadtrip
has the info you need here
... and go from there. https://www.alfabb.com/bb/forums/spi...aq-digest.html
is very helpful. That should keep you busy for a while!