can anyone help me with my program?

The first line of the output is "In function int main()", is it possible that you forgot to close } in the main function? C++ doesn't allow nested procedures.

I am going with evlich here -- you most likely have a {} alignment mistake above the complaint

Here ya go... my program up to the errors.

#include <iostream>
#include <string>
using namespace std;

struct Vehicle
{
int year;
string model;
string color;
int miles;
float mpg;
float gas;
float tank;
};

void displayMenu(int &);

void printVehicle(Vehicle &);
void initVehicle(Vehicle &);

void driveVehicle(Vehicle &);
void refuelVehicle(Vehicle &);
void crashVehicle(Vehicle &);
void readVehicle(Vehicle &);
void paintVehicle(Vehicle &);
bool quit();

int main()
{
int choice;
cout << endl;
Vehicle v1;
initVehicle(v1);

bool done = false;

while(!done)
{
printVehicle(v1);

displayMenu(choice);

if(choice == 1)
{
driveVehicle(v1);
}

if(choice == 2)
{
refuelVehicle(v1);
}

if(choice == 3)
{
crashVehicle(v1);
}

if(choice == 4)
{
readVehicle(v1);
}

if(choice == 5)
{
paintVehicle(v1);
}

if(choice == 0)
{
done = quit();
}

return 0;
}

void displayMenu(int &choice)
{ //THIS IS LINE 86
do
{
cout << "--- CAR SIMULATOR 1.0 ---" << endl;
cout << " 1 --> Drive Car" << endl;
cout << " 2 --> Refuel Car" << endl;
cout << " 3 --> Crash Car" << endl;
cout << " 4 --> Buy a New Car" << endl;
cout << " 5 --> Paint Car" << endl;
cout << " 0 --> Quit..." << endl;
cout << endl << "Enter the number of an option: ";
cin >> choice;
if(choice < 0 || choice > 5)
cout << "unknown command..." << endl;
}while(choice < 0 || choice > 5); //THIS IS LINE 100
}

...(there is more to the program but its left out for space)

yep, looks like the while loop is missing a bracket.

{
int choice;
cout << endl;
Vehicle v1;
initVehicle(v1);

bool done = false;

while(!done)
{
... bunch of matched if pairs
if(choice == 0)
{
done = quit();
}
-------there is no end while here!!
return 0;
}