Install a file archiver that supports RAR files
Windows: use 7-Zip, WinRAR, or PeaZip
macOS: use The Unarchiver, Keka, or WinRAR
Linux: install unrar or use File Roller, Ark, or 7-Zip
Open the RAR file with the installed app
Select Extract or Extract Here
Choose a destination folder if prompted
Enter a password if the archive is protected
Open the extracted files from the destination folder