In your Ubuntu system, if your are getting “Could not create the archive Archive type not supported.” or “There is no command installed for RAR archive files. Do you want to search for a command to open this file?“error when trying to open a rar file, then you need a .rar un-compresser. To uncompress or open a rar file in ubuntu just install unrar and unrar-free.
Install Unrar on Ubuntu
In your terminal app run below commands one by one. You can open terminal by ctrl+alt+t.
sudo add-apt-repository multiverse
sudo apt update
sudo apt-get install unrar
sudo apt-get install unrar-free
Now you can extract and open a .rar file in you Ubuntu system.