Pragha is not available for installation on Linux Mint through the normal channels (Software Manager or clicking the Install button on this webpage). The only way to get Pragha up and running on Linux Mint is to install an external repository on your computer. If you are new to Linux and need further advise on the risks involved with installing external repositories, click on the following link BEGINNERS LEVEL: Install Pragha on a computer running Linux Mint 17.2