How to debug bitcoin core in "real time"
There is no "makefile" command.

If you don't build the project, there is no way for you to debug it. The released binaries do not contain any debugging symbols so it will be very difficult for you to set breakpoints and see what is going on. So in order to do that, you will need to build the project from the source code that you downloaded. There are instructions for how to do this in the docs folder of the downloaded source code.