Installing R and RStudio is usually straightforward. The sections below explain how and there is a helpful YouTube video here.
Install base R from https://cran.rstudio.com/. Choose the download link for your operating system (Linux, Mac OS X, or Windows).
If you have a Mac, install the latest release from the newest R-x.x.x.pkg
link (or a legacy version if you have an older operating system). After you install R, you should also install XQuartz to be able to use some visualisation packages.
If you are installing the Windows version, choose the “base” subdirectory and click on the download link at the top of the page. After you install R, you should also install RTools; use the “recommended” version highlighted near the top of the list.
If you are using Linux, choose your specific operating system and follow the installation instructions.
Go to rstudio.com and download the RStudio Desktop (Open Source License) version for your operating system under the list titled Installers for Supported Platforms.