You may create a new site via the function blogdown::new_site() under an empty directory. It will create a skeleton site, download a Hugo theme from Github, add some sample content, launch a web browser and you will see the new site. The sample blog post hello-world.Rmd should be opened automatically, and you can edit it. The website will be automatically rebuilt and the page will be refreshed after you save the file. If you use RStudio, you can create a new RStudio project for your website from the menu File -> New Project -> New Directory -> Website using blogdown.