I don’t know KiCad library as I use only my libraries. If there is something not there you can always make symbol and footprint yourself. It is easier than designing PCB.
“2 relay module”: you need to make your own Symbol (and Footprint if wanted) for a ‘Module’ but, there are Relay’s in Kicad to start with.
“16 Pin AMP connector” - I was a designer for AMP (now Tyco) and JAE. There are Hundreds of them with commonality and variations but only a handfull in the Kicad Library… You can ‘Hack’ up one or make your own.
For “What’s in Kicad”, learn how to use/search within the Symbol Editor’s main panel - the ‘Trick’ is correct search Words because different things get named differently
For the Connector, do the same thing in the Footprint Editor… and, if a CAD user (of any flavor) you can use my YouTube video as an Overview (and guide to Modeling, and Footprint). First 5 mins is the Modeling, remaining few mins is the Footprint). Symbol making not included…
The ‘Important’ part is the Footprint but you don’t need a 3D Model as they are only for Graphic representation… The Symbol is important for Schematic but, aside from the Pin’s, the rest is symbolic graphics…
If you are using any ebay “module” that is an assembly of parts already on a PCB. Since the module is not a “component”, there is no library symbol (schematic) nor footprint (PCB layout).
Modules are NOT designed to be integrated into/onto another PCB.
You will have to design your own circuit using components.
When I do a module, I make two components: The socket and the actual module.
The socket has the main schematic symbol with all the pins, and has a 3d model with the socket(s). If it is a single sip socket it is easy enough, if it has a couple of sip sockets I build it in freecad.
The module symbol for the schematic is just a little box, and the footprint is also just a box (on user drawings layer, not on silk) the size of the module. The 3d model is the actual module, elevated in z to the level it will sit in the socket. The module can be dragged into final position over the socket, or just off to the side of the board to show what is on the pcb under the socket.
I use ref des Z for the module-socket and ZZ for the module – the module is now on the BOM as it should be. The socket is just a line item on the bom, which then needs to be tweaked to provide the appropriate sip sockets. Not a perfect solution but works for me.
I don’t agree with this. I’ve designed PCB’s with Arduino Pro mini and ESP32 boards.
You will likely need to make your own footprint. The symbol could be a square with the appropriate pins labeled.
CAUTION: If you plan on using a module with the Blue “Songle” relays, folks have found them to be less than reliable. Consider what you will do if a relay fails and the module is soldered to your board.
Not true. Some modules are expressly designed to be integrated on PCBs. I have this GNSS module with castellated holes that’s designed to be soldered onto a base PCB. You would not be able to obtain the module as separate components anyway, that’s how the manufacturer distributes them.