You have both.
If you launch the game via Epic, it will (I believe) ask if you want to launch the DX11 or DX12 version.
Or if you launch it from this trainer, it will launch the DX11 version (or the DX12 version if you launch it from this one instead: Control (DX12) Cheats and Trainer for Epic Games).
DX12 will likely be more resource-intensive than the DX11 version.
Also, DX12 can only run on Windows 10. If you don’t have Windows 10 you’ll need to use the DX11 version.