How do I to insert data into an SQL table using C# as well as implement an upload function?

You should use parameters in your query to prevent attacks, like if someone entered '); drop table ArticlesTBL;--' as one of the values.

string query = "INSERT INTO ArticlesTBL (ArticleTitle, ArticleContent, ArticleType, ArticleImg, ArticleBrief,  ArticleDateTime, ArticleAuthor, ArticlePublished, ArticleHomeDisplay, ArticleViews)";
query += " VALUES (@ArticleTitle, @ArticleContent, @ArticleType, @ArticleImg, @ArticleBrief, @ArticleDateTime, @ArticleAuthor, @ArticlePublished, @ArticleHomeDisplay, @ArticleViews)";

SqlCommand myCommand = new SqlCommand(query, myConnection);
myCommand.Parameters.AddWithValue("@ArticleTitle", ArticleTitleTextBox.Text);
myCommand.Parameters.AddWithValue("@ArticleContent", ArticleContentTextBox.Text);
// ... other parameters
myCommand.ExecuteNonQuery();

(xkcd)

using System;
using System.Data;
using System.Data.SqlClient;

namespace InsertingData
{
    class sqlinsertdata
    {
        static void Main(string[] args)
        {
            try
            { 
            SqlConnection conn = new SqlConnection("Data source=USER-PC; Database=Emp123;User Id=sa;Password=sa123");
            conn.Open();
                SqlCommand cmd = new SqlCommand("insert into <Table Name>values(1,'nagendra',10000);",conn);
                cmd.ExecuteNonQuery();
                Console.WriteLine("Inserting Data Successfully");
                conn.Close();
        }
            catch(Exception e)
            {
                Console.WriteLine("Exception Occre while creating table:" + e.Message + "\t"  + e.GetType());
            }
            Console.ReadKey();

    }
    }
}