The R Graph Catalogue (your second link) has its code available in its GitHub repo here:
Show Me Shiny is powered by wordpress (according to its footer).
There are a bunch of great Shiny tutorials over on the Shiny developer page (below):
https://shiny.rstudio.com/articles/
FYI, I'm moving this into the Shiny category, since it's related to Shiny. However, I think you'll likely need to do a bit more work on your own before the scope of this question is answerable.