SDVOS kernel and system generator are open source software published under GPLv3. You can download the source code from github. However, before downloading the source code, please take a look at the tutorials and specifically the download section.
If you are new to OSEK/AUTOSAR standards and RTOS in general, I highly recommend you spend some time in tutorials and documentations. To experience all the capabilities of the SDVOS kernel, I recommend using the NUCLEOF401RE reference board. However, you can give SDVOS a try even if you don't have the hardware. You can run SDVOS as a process in Linux.