If you want to work with Gambas, you should install the development environment Gambas on your computer. There are four alternative ways to install gambas, for example for the Linux distribution Ubuntu and its derivatives:
For other Linux distributions, the second variant is the most promising one if the installation from the package sources of the Linux distribution used is not possible, the version is faulty or outdated. Whether you choose to use a stable version of Gambas or the development version depends on the goals you want to achieve.
Good to know for nostalgics: You can convert a Gambas2 project (semi-automatic) into a Gambas3 project in the development environment of Gambas3.