04 PT Cruiser possible oil issue after overheating problem

This may be slightly long but, bear with me. I'm not
sure what details about the car's previous state will
help shed light on the answer to my problem so, I'll
start from the beginning.
Bought the car in March with ~170,000 miles. Ran
great. Seemed to have no issues. Within a couple
of months, a.c. started to go out. Eventually, it
wouldn't blow cold or cool air then not long after
that, started overheating when idling sometimes
with or without a.c. on. Then, started overheating
unless it was drove at a high enough speed to cool
it off. Then, would overheat no matter what (even
with heat on full blast, etc.) Thought the problem
was my high relay. Bought a new cooling fan and
same issue so, took it back and got a wiring
harness kit just in case it was a bad connector and
never got around to installing it. No other vehicle
and I'm in school so, continued to drive it while
dealing with it overheating every so often until one
day the check engine oil light came on while it was
overheating and the engine shut itself off. My
Papaw worked on it and said he fixed the fan, a.c.,
and overheating issue. Drove perfect for about 40
miles then same thing happened again. (Should
mention I changed my oil maybe a month before
this.) Decided to look at it myself after he "fixed" it
once more and it again drove fine for 40 miles or
so then engine shut itself off again with the check
engine light on and it overheating. My serpentine
belt was completely off. Apparently, when it was
replaced before my a.c. started going out because
my power steering was out one day, it wasn't put
on properly and had been off for I don't know how
long. Got it put back on and filled my radiator with
water (I had been having problems keeping it filled,
due to overheating I'm sure and didn't want to
water any more money on coolant if it was still
going to do it) and correctly pressurized it with the
valve, which I'm positive no one else had been
doing when they were working on it. Correct me if
I'm wrong, but do you not need to use the valve to
let out excess air in radiator for pressure to be right
or will radiator work out the air on it's own? Either
way, once I did all that, I had no problems driving it
for almost a day. When it finally died, it felt like it
wss accelerating itself a little then it backed off
and sounded like it was going to die then
accelerated again and repeated that process
probably 3 times then turned itself off and started
smoking badly. When I looked underneath it, there
was oil everywhere on the bottom side of the
engine. Sorry, I'm not entirely mechanically inclined
and the diagrams I've found don't seem to match
up to what I was looking at so, I don't know what
parts exactly the oil was on. I checked my oil level
3 or 4 times over the next couple days and it was
the same as before, right below max. Now, it has
been sitting for a week and the oil level is at
minimum and when I try to start it, it's a whining
sound that it makes and it doesn't sound like it's
trying to turn over at all. I took pictures of what I
thought the issue is. There's a part that seems to
not sit correctly on the piece it's connected to. I'm
trying to figure out what that piece is and also if I'm
wasting my time trying to fix it because my engines
blown.
Side note: when I put my serpentine belt on, I
noticed my air filter was filthy so I sprayed it off
and let it dry some and put it back in. I didn't know
you weren't supposed to get them wet. It wasn't
soaking wet but, it was slightly damp still. I'm not
sure if that's relevant to my problem or not.