Overview of Kicad

Kicad is a Free Sofware application to design PCBs
It covers both schematic design and PCB drawing
It's getting pretty complete over the years
Unfortunately, it means it's getting a little more complex too

The main schematic tool is called "eeschema"
Schematic files, called "*.sch", are ASCII texts
It relies on a library of components
There is a rich default library of components
More components are found online, with a free license
You can design yours, as usual

The PCB design tool is called "pcbnew"
The file is called "*.kicad_pcb", and it is an ASCII text
It relies on a library of footprints
There is a rich default library of footprints
More footprints are found online with a free license
You can design yours, as usual