How do you insert an object into a database

 How do you insert an object into a database, here is the object from the class:
public static Int32 InsertBaseCar(BaseCar theCar)
{
Int32 newBCarId = 0;
try
{
SqlConnection cn = new SqlConnection(_connectionString);
SqlCommand cmd = new SqlCommand("sp_InsertBaseCar", cn);
cmd.CommandType = CommandType.StoredProcedure;
cmd.Parameters.AddWithValue("@id", theCar.ID);
cmd.Parameters.AddWithValue("@make", theCar.Make);
cmd.Parameters.AddWithValue("@model", theCar.Model);
using (cn)
{
cn.Open();
newBCarId = Convert.ToInt32(cmd.ExecuteScalar());
}
}
catch
{
// write code here.
}
return newBCarId;
}
And here is my attend at inserting the code into the database:
public void InsertBaseCar()
{
BaseCar theCar = new BaseC ...