install.packages("renv")
renv::restore()This should install all necessary packages.
If it doesn't work, try to run the library statements in the first chunk in index.Rmd where all packages are loaded and install those that you are missing.
in the R console
bookdown::render_book('index.Rmd', 'bookdown::gitbook')or use the shortcut for knitting (Ctrl+Shift+K / Cmd+Shift+K) while having open any of the Rmd files.
For working locally on the book, you can also serve the book by running
bookdown::serve_book()
in the R console. This will start a server on localhost:4321 where you can see the book and it will update whenever you change (and save) a Rmd file.
https://devguide.ropensci.org/ and repo: https://github.com/ropensci/dev_guide/