Laravel select one image from every row from database - database

Question

I have 2 tables in my database , one with cars and one with images for cars..is a one to many relationship..A car can have multiple images , but I want to select for every car just one image. The 2 tables are
Car table:
Schema::create('cars', function (Blueprint $table) {
$table->id();
$table->string('model');
$table->integer('seats');
$table->string('fuel');
$table->integer('year');
$table->string('color');
$table->string('gearbox');
$table->integer('price');
$table->string('coinType');
$table->timestamps();
});
Images table:
Schema::create('images', function (Blueprint $table) {
$table->id();
$table->integer('car_id');
$table->string('file_name');
$table->timestamps();
});
class Car extends Model
{
protected $fillable = [
'model',
'seats',
'fuel',
'year',
'color',
'gearbox',
'price',
'coinType',
];
public function images()
{
return $this->hasMany(Image::class);
}
Image model:
class Image extends Model
{
protected $fillable = [
'car_id',
'file_name'
];
public function car()
{
return $this->belongsTo(Car::class);
}
I tried to make a join between tables like that:
$images = Image::join('cars', 'images.car_id', '=', 'car.id')
->select('images.file_name')
->first();
But I get only the first row from that table. I need some help here, Thank you