eduActiv8 is written in python which is an interpreted language therefore in most cases it can be run from source after installing some required software. Depending on the OS some of that may already be installed. If running from source is not your thing, there are packages already created for Windows, MacOS and Linux (not sure about how cross platform the Linux version is though – it has been build on 64 bit Ubuntu 16.04 so will probably run on a similar machine or newer, failing that it may as well be easier to just run from source).
To run a package there is no installation required as such. All you need to do is to download the correct version of eduActiv8 for your operating system, unpack and double click on the executable: eduactiv8.exe on Windows, eduactiv8.app on MacOS, and eduactiv8 on Linux. Just for ease you can create a shortcut to the program if you like.
The Android version can be installed directly from here: eduActiv8 for Android