will Pokemon database inform me if there are any of new codes or will I have to visit some website is what I am looking for
“ it has never done that so I don´t think so” - Ether Eevees
It’s never done it before and likely never will. Just google “Pokemon”, look at Pokémon.Com, or Bulbapedia and you’ll see the news.
The website known as Serebii.net shows the event Pokemon and event raids for Pokémon Sword and shield so I will recommend checking the website out.