I want to simply render a 2D image to the window. After hours of digging into DirectX, still can't find a way to do it. Can I simply load the image into buffer then let swapchain to display this buffer of image?
The SimpleTexture sample on GitHub demonstrates exactly this scenario for C++.
As you are new to DirectX, you may also want to look at the DirectX Tool Kit for DX11 / DX12 which provides a very simple to use SpriteBatch class.