Failed to read dockerfile error

While building image, I encountered a “Failed to read dockerfile” error.

I am learning to build Python image using the example in

I have kept the files as the below snapshot. When I run the command in Powershell as below I found the error.

ERROR: failed to solve: failed to read dockerfile: open /var/lib/docker/tmp/buildkit-mount3948669650/Dockerfile: no such file or directory

What am I doing incorrectly?