How to get sonic adventure for PS3?

You can't get Sonic Adventure for the PS3. It was released for the Sega Dreamcast and later ported to PC.

There are a few options if you want to play Sonic Adventure:

* Emulation: You can emulate the Dreamcast version of Sonic Adventure on a PC. This requires downloading an emulator and the game's ROM file.

* PC Version: You can purchase the PC version of Sonic Adventure from online retailers like Steam. This version includes some updated graphics and features compared to the Dreamcast version.

* Sonic Adventure DX: A re-release of the game called Sonic Adventure DX was released for GameCube and later ported to PC. It includes improved visuals, gameplay tweaks, and new features like the "Chao Garden."

Keep in mind that using ROMs and emulators might be considered illegal in some regions.

If you want to play Sonic Adventure on a console, the only option is the Dreamcast. You can find used Dreamcasts and copies of the game online or at retro game stores.