Is it possible for anybody to be expert in all areas of software development, that includes database, backend, web frontend, mobile apps, and graphic design?
It isn’t possible for someone to be expert in “all” aspects of software development—that would include everything from writing safety critical control systems for nuclear power plants in Fortran to high frequency trading algorithms on Wall Street. The world of software development is simply too big for that now.
It is possible for someone to become an expert on “database, backend, web frontend, mobile apps, and graphic design”. Programmers who excel at all of those with the exception of graphic design are sometimes known as “full stack” developers, although mobile apps are usually a seperate speciality.
People who also excel at graphic design do exist but are very rare. I’ve known a few and I’m always pretty jealous of them!
This answer does of course vary depending on how you define the word “expert”.