At the beginning of the universe, there was just a bunch of particles flying around in a hot soup. One part of the universe was barely distinguishable from any other.
For 14.8 billion years that soup of particles has been doing an elaborate dance — jumping around, constantly reconfiguring themselves, getting locked into clumps of matter that are changed and mixed by the laws of physics.
This dance could have led to countless different configurations, but they arrived here, to you reading this.