Responsive Background Image

Hello,
I have a problem with the adaptive background image (1080x1920).
I tried to do it myself, but there are two problems:

  • In the first case, the image fills all the empty space on the screen, but does NOT keep the aspect ratio.
  • In the second case, the image keeps the aspect ratio, but black blocks appear.

I solved this problem by enlarging the image itself, but this is not the best solution that can be.
The task is to make the image adapt to the size of the screen without leaving black blocks, but keeping the aspect ratio.

Here are some notes on UI Anchoring, Scaling, CanvasScaler, etc: