Welcome to CYS! As DerPrussen said, EndMaster's stories are a great place to begin - my personal favorite being Death Song, which can be found on the featured list. I would also like to recommend Crescentstar's stories, which are also very well written.
If you would like to get engaged with the writing community here, we occasionally do all sorts of fun contests and such, and we are always looking forward to new short stories over at Creative Corner! Once you get a feel for how things work, you can even try your hand at writing a CYOA.
I look forward to seeing you on CYS!
Oh yeah, you should speak to Gower (the dude above me), he can help you more than anybody else here.