Well, looks like you're going to need some glass to begin with...
On gas...unleaded is fine as long as it does not have ethanol added. It is possible to switch the various systems over to use gas with ethanol, however that is a rather expensive proposition, from new hardened valves to converting any and all rubber in the fuel system to newer, alcohol resistant versions. I'm sure someone here can give you a complete rundown on all that's involved for that conversion. There is a website that will pinpoint stations that still have non-ethanol gas throughout the country:
www.pure-gas.org which will identify those stations in your area. Personally, I would recommend adding an octane booster (available at your local parts supply house) as these engines do operate better at a higher octane level.
Another option, and one I recommend, is to contact any local regional airport in your area. They should have 100 octane low-lead AV gas available. It is more expensive, about twice what you'll pay at the local pump for non-ethanol gas, but it is far closer to what you would have bought in '51 from the local filling station when your choices were 'Regular' and 'Ethyl'...and no I'm not talking about Ethyl Mertz. Unfortunately, you don't get the 5 guys in bright white racing out to fill your tank, check your oil, fill your tires and wash your windows.
They may require you bring gas cans to obtain it, or if you're lucky, they'll let you drive right up to the fueling pad and fill up, as my local regional port does.
I would definitely consider a complete tune up as being in your future. There is a club member in New York who makes excellent repro plug wires, and all the rest of the parts are readily (and cheaply) available from NAPA or Ebay. Do a search on a previous post I made inquiring what was needed for such a tune up...other forum members gave me precise parts numbers for my tune up...but definitely do a compression check as well...there are new intake valves in my future plans as my tune up revealed one cylinder at only about 80 PSI. It's not critical at this point, but I do want my baby to run with peak efficiency down the line.
My guess is you will need a new battery. You haven't said how long it's been since this car was on the road, but given the condition in your pic, my guess is that it has been a while...barn find perhaps? Is it manual or hydramatic auto trans? Overdrive if manual? Either way, you may find the seals have dried out over the years and probably leak. Once you get it on the road and drive it some, those seals may rehydrate to some extent, but I would plan on at least some work on the tranny in the future.
Brakes...definitely check those out...muy bad juju to have bad brakes or a weak system when you do get it on the road.
I'm sure others here will chip in with more suggestions. I'm a relative novice to these cars myself, having just bought mine back in January. It was a garage/trailer queen for about 20 years before I got it, and I've had about a grand's worth of work done on her to make her road worthy...or rather, what I consider road worthy...with more to come to get her up to what I consider mechanical snuff for my taste and needs.
All that said, please join the KFOCI...the info you will have access to by joining the club is invaluable. It's cheap, helps keep the club going, and is worth its weight in gold as far as these interesting beasties are concerned. There are people here who will go out of their way to help you along on your journey of getting your beastie back on the road...the folks here are salt of the earth helpful and will not steer you wrong. I've (as a recent convert to KF cars) perhaps asked many of the questions that are likely percolating through your mind as you look to restore your beastie to driving condition...search them out and I'm sure the responses will be as helpful to you as they were to me.
And welcome to owning a small piece of amazing American ingenuity, design and engineering...you won't be sorry.