Choose the platform you will be using (ex. Windows 7, 8.1 10, Mac OS, etc.) and language
I would suggest not to choose android, ipad, chromebook or fire tablet as you will not get the full version of the software with these platforms.
Then click Download
If you are asked to choose "student" or "educator" version, either works. The educator/teacher version may give you access to lessons, but there are tutorials in both versions.