A great idea

I have a friend,Nancy. We often go together by bus to  bookshops. Yesterday,we decided to go to a new bookshop. But when we got to the bus station, we found there were lots of people. Twenty minutes passed,a bus arrived at the station. We got on the bus.
"I think this is the most crowded place in the world！", I said to Nancy.
"I think so.}, she said.
We tried to find seats,but we failed.  It was   too crowded！We could only stand.
After a while, a old man got on the bus. He was very old but he couldn't find any seat.
"Look at him！", Nancy said to me. "How old do you think he is？“"
"At least eighty！", I said decisively.
"I do not think standing is good for him.What can we do for him？", she asked.
"I don't know.", I answered.
After seventeen minutes, I heard the old man say "I can't get off ! ".
"Why？", I thought.
"The crowd is blocking the door !", he said.
"It is so crowed that he can't get off.", I said.
"Well, I have an idea.", Nancy said.
We always take this bus, so we know the driver‘s phone number. Nancy called the driver and told him about her idea. Soon after,the driver put  the brakes on suddenly. All the people  fell back. When they asked him for why, Nancy shouted to old man.
”You can get off！“
By then, I saw that  no one stood near the door. They all  had fallen  into  the back of the bus. So that old man could get off！

”“ <-- these marks are not the standard quotation marks.  Use ".

Leave a space after a punctuation mark like a comma or  a full stop.

I have added a comma after some of your segments of speech as the sentence includes things like "he said" "I said'

This is a good effort displaying a range of vocabulary with really very little that needs correction.