|Hello LJ Apollo, PM here to review your story.
I like the idea. It's a fascinating concept.
The first two sentences are run-on sentences. There are run-on sentences throughout the piece. I would recommend breaking them up.
You have a lot of punctuation errors. I have put the corrections in parentheses. "(T)then" means you should capitalize the following word:
As he crossed the room to another door(,) I deduced this room had not lived up to its potential for quite some time.
Unlocking the second door and opening it inward(,) gesturing for me to enter first, I obliged and upon going in(,) I saw nothing at first(.)(T)then a shallow light hum began and several rows of florescent (misspelled) started to come to life,(should be a period) (T)the room was pristine,sanitizer white(,) and you could start to make out the medical apparatuses surrounding a surgical table,(should be a period) (A)a few of the machines were bumping and whirring and you saw the IV bags hanging on the rack next to the table by a corpse, but the configuration of the body was way off,(should be a period)the head was oversized,the arms much too long situated atop a bloated torso.As my eyes adjusted to the site (should be sight) of the strange corpse on the table(,) I quickly surmised this was not human or animal of this world.
"WHAT (You generally shouldn't put words in all caps. To place emphasis you could italicize)the hell is that(?)"I turned and asked our host? (Question mark should be after "that")
He just smiled,"(W)well(,) that depends on how you want to describe it,(Should be a period) (P)please have a seat and I'll try to explain it to you."
Ushering me over to a stool by one of the labs work tables(,) I sat and kept my eye fixated on the new creature behind my guest.
"Would you like some coffee,I think you'll need a cup of coffee"?!(Question mark and exclamation mark should be after "coffee")
Simply nodding at the question(,) my mind ran the scenario in my head of the new situation,(should be a period) (A)as he returned from a small break room in the corner of the lab he brought with him two cups of coffee(.) (H)he sat(,) smiled and began. (Should be :)
"Of course you heard(a space is needed here) of area 51 and all the UFO stuff from the 50(')s(,) and until now(,) most of it was rubbish! The origin of our friend here is a little more discreet,when he was found he was alone.
He was discovered during a camping trip in the Canadian mountains near the Ontario Providence(.) (H)he was brought to a secure safe facility about 40 miles north of Vancouver,(.)(T)there he was tended to and nursed back to shape,(.) (W)we shortly learned his communication abilities were phenomenal,(.) I think he has some kind of psychic ability and he eventually could communicate enough to explain how he came to be.
He was more of an explorer or a scout searching for a new home for his world(.) (H)his world was in peril due to an eminent supernova, so he was seeded here but soon realized the habitation of this planet and his people could not coexist,(.) (H)he tried to contact the others(,) but it was to(o) late ,(.) (A)a huge eruption of his sun occurred and the expected supernova took out his world.He with (should be "was) stranded(,) left alone,(.)(H)he know he could not exist in this world(,) so he fled to the Canadian mountains to avoid contact,(.)(H)his solitary existence soon proved problematic and there was an accident(.) (H)he was injured and could not take care of himself,(.) (I)injured (and) alone(,) he surrendered himself to death(,) only to be discovered by the camping party. After his rescue, he began to show his gratefulness that the humans had shown him by sharing some of his advanced technologies(.) (H)he began working with some of our technicians,(a space is needed here)physicists(,) and medical scientist showing them new forms of perceptual thought transformation,(.) (H)he could literally put himself and his consciousness in a host body,(.)(U)unfortunately for the host they were left in a state of suspension in his mind because the human mind was not as complex as his."
Sipping on our coffee and me still fixating on the creature he continued,"Now his shell is hardly existing to maintain any brain activity left(.) and that(,) my dear(,) is why you are here."
He set his coffee down and produced a dry(,) thin lip smile at me.
"ME"??, I quickly questioned,"I don't have any experience in alien medical procedures or the scientific medical makeup to produce any viable help for your friend."
Suddenly I was lightheaded and I was blaming the stress of the new situation.
I hope you find this helpful, and keep writing!