Fairly new to KiCad; I’ve been scouring this forum this whole week and have gotten a bunch of help. I’m still unsure how to connect traces to the components. The airwires will show one connection but i feel like that’s not the connection that I need in order for the circuit to work properly. My thinking is thaat when making the traces, i should following the schematic, but I can’t connect to the pins that I want if it’s not already connected through the airwires. I also put in my GND planes but am unsure how to check if my pins that need to be connected to the GND are connected.
If you have made changes to the schematic make sure they are updated on the PCB. In Schematic editor, press F8 (Update PCB from schematic)
You should be able to route a track where the air traces are on the PCB.
The GND from the battery charger should be connected to the GND from the Arduino.
Also helpful if you show the version (Help / About KiCad / Copy Version info)
I am running KiCad 8.0
Those “Airwires” are called a ratsnest, and those are the same connections as in the schematic. Do note that in the schematic, pins are in a “logical order” that is pleasant to the eyes, and easy to understand, while on the PCB, the pins have fixed physical locations in the footprint. If you make a change to the schematic, then use Schematic Editor / Tools / Update PCB from Schematic [F8], then the ratsnest gets updated to reflect the changes you made in the schematic. Just compare the connections in the schematic, and on the PCB ( + Ratsnest) and you will discover they are the same. If you gain more experience, you will learn to trust this. You can also use: PCB Editor / Inspect / Design Rules Checker to check the status of your PCB.
Yes, and that is how it should be. The ratsnest reflects the schematic connections, and KiCad (by default, (it can be overruled)) will not let you make connections that are not in the schematic. You have a lot of unconnected pins in your schematic (all correctly marked with a “No Connect” cross).
Your GND plane does not look good. It shorts all pins of all footprints, and that is something that should not happen. How did you draw that ground plane? Which functions did you use? You should have used: PCB Editor / Place / Add Filled Zone [Ctrl + Shift + Z] This also brings up a context window with settings for the zone, including a selection option for the net to connect the zone to.
I also see a few ERC arrows in the schematic. So you have run ERC at least once, and that is a good thing. But what are the ER messages KiCad generated?
You can see that KiCad attempts to connect both pins 4 and 29 to the GND zone, and all pads that should not be connected now have a clearance around the pad, so that is good. The routing itself is not so good. To the right of pin 4 you have created an island under A9 (the arduino thing) and that apparently does not count as a valid thermal spoke connection. On the left side the zone is only connected to the “rest” under the push button, which is also far from optimal. On PCB’s like this, usually only one side has a GND zone, and the other side is used for signal (and power) routing. If needed, small hops are made to the other side (which interrupt the GND zone) and those interruptions should be kept to a minimum (both size and number).
I’m not quite sure what that means. How would I get rid of the island. And when you say the “other side” are you talking about the B_Cu plane?
The “Island” is the part of the GND zone under the center of the arduino. Zoom in and look at it more closely. It is only connected through pin 4 of the arduino (So it’s not really an idland but a peninsula).
With the “other side”, I mean this area:
The hatched area is barely connected to anything, because a few tracks that cut though the zone cut it off and isolate it from the rest. This should not happen in a PCB design.
Ok I see now how the ground is cutoff. So I don’t want that small bit of ground through pin 4 and I should keep the ground all on one side? And to do that I would need to reroute the traces?
Indeed, something like that, but then the track cuts though the zone on the other side, and what is that connected to?
For relatively simple PCB’s such as this, generally the best approach is to dedicate one layer to GND, and do all other connections (both signals and power routing) on the other side of the PCB. The reasons for this have to do with frequency dependent behavior of currents though the GND plane and the other tracks. This is a bit of a complicated subject. Rick Hartley (from altium) has made some great video’s about this (available on youtube), but I guess they are a bit much for you at this moment (the video is just over two hours long).
So I’m an hour in the video and I’ve learned things. I think I understand now what you mean by separating the signals and GND connections on separate planes. So do i need to create a new plane for the signals? Because when going through the tutorial of creating a GND plane, I was instructed to make both the F_Cu and B_Cu planes to be GND.
I have a link here for a very good tutorial on the basics of Kicad I used it years ago and other people liked it so when your not sweating into the keyboard try watching this guy https://youtube.com/playlist?list=PL3by7evD3F51fKkyrUbH-PCdwPCWc9F8a&si=dlXyq2wjZpXSKNZa 
I think starting from scratch and following the guy would be useful and the project he walks through is a power supply for breadboards that is great for powering up Arduino projects 
so you might have something useful at the end but you will have learnt a lot about Kicad.
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No, that is not needed. One good GND plane is enough for all “beginner stuff”. When you start designing FPGA stuff or boards with DDR3 or faster memory then signal integrity becomes more of a concern. (To be correct: it is the flank steepness (and thus the sort of IC’s used) that determines the frequency content of the signals. It’s not the signal frequencies used in the circuit.
I don’t know what sort of tutorial that was, and what the intended audience for that tutorial was, but it probably does not apply here.
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I always have GND plane at both sides, but only one of them is continuous (no other tracks at this side). At the other side I have many GND islands and don’t care about it, but each island i connect with some vias to the GND on the other, continuous GND side.
Example you can see here:
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