Using Rmarkdown to create website

I am new to creating website using Rmarkdown
I was able to build a simple website as follow:.

I want to make my website similar to rmarkdown page https://rmarkdown.rstudio.com/lesson-1.html

so that when I click the first link normal distribution, the content would come up and replace the document image instead of redirecting to a separate tab, and the URL would point to Normal.html; when I click the second link, the content of Paired T-test would replace the document image and the URL would indicate T-test.html and so on.

I have forked the rmarkdown rstudio site and found its github pages do not originate from the master branch, but from the gh-pages branch indeed.....

I tried to navigate the codes, it seems like the framework of the "Get started" menu is defined in _pkgdown.yml, but as a beginner it's not so easy for me to fully understand it.

I just wonder can I simply integrate put _pkgdown.yml on the folders in master branch and use Github desktop to commit and push the changes and achieve what I want?

I have been searching whole day and couldn't find any example on the web.

I have even tried to read bookdown site , but it seems like not what I am exactly looking for.

Would anyone please kindly shed some light or guide me to the proper material?

Looking forward to any comment. Thanks so much!

brgds,
Millie