Bulk insert into the SQL Server 2012 database - C#

I have about a million of records in the list. And foreach in the list I query the database to get the modified date based on id. Once I get it, it's test in the condition to either insert it or update it .. but is there any way to do it as bulk (at once or in batches) insertion or update..??

foreach (No_kemi no_list in newforSQL)
{
    DateTime eModifiedDate = no_list.ModifiedDate.Value;
    string Id = no_list.ID.ToString();

    String selectQuery = "SELECT ModifiedDate FROM NO_table WHERE ID = '" + Id + "'";
    DateTime? dbmoddate = null;

    using (SqlCommand selectCommand = new SqlCommand(selectQuery, connection))
    {
        // Use the above SqlCommand object to create a SqlDataReader object.
        using (SqlDataReader rdr = selectCommand.ExecuteReader())
        {
            while (rdr.Read())
            {
                dbmoddate = (DateTime)rdr["ModifiedDate"];
            }
        }
    }

    string eType = null;
    string SubGUID = null;
    string trimSubKey = no_list.SubscriberKey;

    try
    {
        if ((trimSubKey.Length > 3) && (trimSubKey != ""))
        {
            if (trimSubKey.Contains(","))
            {
                string[] values = trimSubKey.Split(',');

                SubGUID = values[0];
                eType = values[1];
            }
            else 
            { 
                SubGUID = trimSubKey; 
                eType = ""; 
            }
        }
        else 
        { 
             SubGUID = ""; 
             eType = ""; 
        }
    }
    catch (Exception ex)
    {
        logger.Error("Error : " + ex.Message );
    }

    if (dbmoddate == null)
    {
        DateTime no_listinsetdate = DateTime.Now;
        String insertQuery = "INSERT INTO NO_table (CreatedDate, ModifiedDate, ID, eType, SubGUID, DbDate) VALUES (@CreatedDate, @ModifiedDate, @ID, @eType, @SubGUID, @DbDate,)";

        using (SqlCommand insertCommand = new SqlCommand(insertQuery, connection))
        {
             insertCommand.Parameters.AddWithValue("@CreatedDate", no_list.CreatedDate);
             insertCommand.Parameters.AddWithValue("@ModifiedDate", no_list.ModifiedDate);
             insertCommand.Parameters.AddWithValue("@ID", no_list.ID);
             insertCommand.Parameters.AddWithValue("@eType", eType);
             insertCommand.Parameters.AddWithValue("@SubGUID", SubGUID);
             insertCommand.Parameters.AddWithValue("@DbDate", no_listinsetdate);

             insertCommand.ExecuteNonQuery(); // execute the query
         }
    }
    else if (eModifiedDate > dbmoddate)
    {
        DateTime no_listinsetdate = DateTime.Now;
        String updateQuery = "UPDATE  NO_table SET CreatedDate = @CreatedDate, ModifiedDate = @ModifiedDate, ID = @ID, eType = @eType, SubGUID = @SubGUID, DbDate = @DbDate WHERE ID = '" + Id + "'";

        using (SqlCommand updateCommand = new SqlCommand(updateQuery, connection))
        {
            updateCommand.Parameters.AddWithValue("@CreatedDate", no_list.CreatedDate);
            updateCommand.Parameters.AddWithValue("@ModifiedDate", no_list.ModifiedDate);
            updateCommand.Parameters.AddWithValue("@ID", no_list.ID);
            updateCommand.Parameters.AddWithValue("@eType", eType);
            updateCommand.Parameters.AddWithValue("@SubGUID", SubGUID);
            updateCommand.Parameters.AddWithValue("@DbDate", no_listinsetdate);

            updateCommand.ExecuteNonQuery(); // execute the query
        }
    }
}

any way to speed up the process... it takes lot of time to finish the operations... or some time I get timeout error ...

thx