can you help me with my grammar?

Question

Can you help me?
Please help me correct the grammars of this paragraph:

They’re still familiar with the facilities of the school. There is no other human presence inside. It’s only the three of them. They are wandering and to find the exit. The group is currently on their old classroom at the 4th floor and they just have to go downstairs to the exit at the ground floor. They are at the last few steps of the staircase when they saw a corpse. “Calvin?” Burt said in a shocked way. He was skin is damaged by a third degree burn. Half of his face can’t be recognized because extreme burns. Men are not supposed to scream and run like girls but they did. Carlos and Rowdy rushed downstairs faster and that makes Burt left behind. The floor is slippery because of a liquid substance. Burt fell down; his nosed smelled the scent of kerosene from the solvent that wets the floor. He is about to stand up when he heard a very angry voice. "It's going to be your doom pretty boy!" Burt saw a very familiar face, It's Mario Solo, The skinny boy they had put through hell, the kid who had a miserable social life because of what they had done to him. He is now stronger, more fierce and his madness wants some payback. "It's to late! You can run to any room but you cant get away from me...pretty boy!" Mario growled. Burt tried to crawl away to run for his life but it's too late. Mario had pulled the trigger of his flame thrower. The kerosene is a fuel that can ignite flames. "no!" Burt screamed as Mario incinerates him alive. "This is the payment I always wanted for years!!" Mario laughed in ecstasy. Burt's flesh was almost peeled out from the third degree burns. "Please stop it..."he moaned.

Answer 1

They were still familiar with the facilities of the school. There was no other human presence inside, only the three of them. They were wandering around and trying to find the exit. The group was currently in their old classroom on the 4th floor. They had to go downstairs to the exit on the ground floor. They were at the last few steps of the staircase when they saw a corpse. “Calvin?” Burt said in a shocked way. His skin was damaged by a third degree burns, half of his face couldn’t be recognized because of the extreme burns. Men are not supposed to scream and run like girls but they did. Carlos and Rowdy rushed downstairs faster and Burt was left behind. The floor was slippery because of a liquid substance. Burt fell down; his nosed smelled the scent of kerosene from the solvent that wets the floor. He was about to stand up, when he heard a very angry voice, "It's going to be your doom pretty boy!" Burt saw some very familiar faces, it was Mario Solo, and the skinny boy they had put through hell. The kid had had a miserable social life because of what they had done to him. He was now stronger, fiercer, and his madness wanted payback. "It's too late! You can run to any room, but you can’t get away from me, pretty boy!” Mario growled. Burt tried to crawl away to run for his life but it was too late. Mario had pulled the trigger of his flamethrower. The flames ignited the kerosene. "No!” Burt screamed as he began to burn alive. "This is the payback I wanted for years!!” Mario laughed in ecstasy. Burt's flesh had almost peeled from the third degree burns. "Please stop it,”he moaned.

Answer 2

They’re still familiar with the facilities of the school. There is no other human presence inside. It’s only the three of them. They are wandering to find the exit. The group is currently on their old classroom at the 4th floor and they just have to go downstairs to the exit at the ground floor. They are at the last few steps of the staircase when they see a corpse. “Calvin?” Burt said shocked. His skin was damaged by a third degree burn. Half of his face couldn't be recognized because of extreme burns. Men are not supposed to scream and run like girls but they did. Carlos and Rowdy rushed downstairs faster and that made Burt left behind. The floor was slippery because of a liquid substance. Burt fell down; his nose smelled the scent of kerosene from the solvent that wets the floor. He was about to stand up when he heard a very angry voice. "It's going to be your doom pretty boy!" Burt saw a very familiar face, It's Mario Solo, the skinny boy they had put through hell, the kid who had a miserable social life because of what they had done to him. He is now stronger, more fierce and his madness wants some payback. 'It's to late! You can run to any room but you can't get away from me...pretty boy!' Mario growled. Burt tried to crawl away to run for his life but it's too late. Mario pulled the trigger of his flame thrower. The kerosene is a fuel that can ignite flames. "No!" Burt screamed as Mario incinerated him alive. "This is the payment I always wanted for years!!" Mario laughted in ecstasy. Burt's flesh was almost peeled off from the third degree burns. "Please stop it..."he moaned.

Answer 3

It's tooooo long. I want to get onto other, shorter questions.
.

Answer 4

is there any shorter passage ?..