I just have two power pins connected to a global label, and the label to the cap to the step-down regulator. The docs for the reg. says it MUST be connected through a very specific cap, which must be as close to the reg pin as possible. (It also requires a cap on the power output pin as well). So I feel comfortable that it is right, but it says there is no power going to the input pin on the regulator.
Yes, you need to look at it.
Alright! Figured it out! The little red flag near the U2 Bi Vin pin says THIS. So does the little red flag opposite.
Please take a second to read the advice that people are giving - there is an awful lot of experience here.
DC can not flow through a capacitor, so datasheet or not, your statement on their position is wrong. Looking at the datasheet, it makes no such statement - take a look at the example schematic at the bottom left of page 1:
Note that the capacitors (which are known as decoupling capacitors) are between the power inputs / outputs and ground. In general terms, capacitors let AC flow, but not DC. Their job here is to let noise from the regulator flow to ground and not in to the circuitry connected either side of the regulator.
greybadger26 posted useful diagram but, so you won’t feel I ignored you, below is another image (I assumed were talking DC through USB as they don’t (typically) do AC but, who knows what you’re doing… (not me)…
A general arrangement for using Regulators for powering/smoothing signals
This example might help. It’s a circuit to convert a +5 V USB power to +/-5 V.
All power inputs need a source, either a real power output or an imaginary PWR_FLAG.
OK, well that’s completely wrong - you appear to have misunderstood the requirements. Current cannot flow into U2 through that capacitor on VIN.
Read the replies above this one in order to learn how the capacitors should be connected.
Have you tried reading that sentence back? It won’t parse; I have no idea what it means and I don’t believe anyone else will be able to make sense of it, either. We cannot help if you won’t take the trouble to communicate clearly.
With respect, I think you need to take a breath, read the replies you’ve had so far, and in particular do us the courtesy of expressing yourself clearly, thoughtfully and respectfully.
In your first post you have written:
And I believe Getting started manual contains information how to make connections. So if you have a problem with making connections at schematic then you probably didn’t read it. So:
I was writing only about need to read Getting started manual. I am very surprised where you found any note about you don’t knowing how to read.
In the following chapter:
there is described how to use PWR_FLAG symbols to avoid this error.
Again: Start with something simple to get to learn KiCad.
Also, posting with only the text “HERE” does not help your cause.
I have mostly tuned out of this thread, because it’s a lot of buzzing around in circles and miscommunication, and I have no interest in figuring out what might be going on in these 28 posts.
Explaining your problem, and asking the right questions is also an important part of a forum. There is no face to face contact, communication forth and back is slow because we have to read posts etc.
I suggest you start here:
https://www.catb.org/esr/faqs/smart-questions.html
In the “Basic Concepts and Workflow” chapter (at the beginning of Getting started) the nomenclature used in KiCad is described.
Two quotes from this chapter:
“The schematic contains symbols for every component in the design, with wires connecting pins in the symbols.”
“The board is the physical realization of the schematic, with component footprints positioned on the board and copper tracks making the connections described in the schematic. Footprints are a set of copper pads that match the pins on a physical component.”
So when you write ‘as close to the reg pin as possible’ at first I understand you are speaking about schematic. Assuming that being new to KiCad it is possible that you used pin instead of pad by mistake I admit the thought that you were really thinking about PCB. But then seeing how at schematic you connected that capacitor to IC (and not knowing if you even started to design PCB (I see only pictures in the thread)) I am back with my guess that writing this you were thinking about schematic.
I still don’t know what is the crux of the OPs problem with KiCad. From first post I supposed he has problem with drawing wires. Now I suppose he is overwhelmed by the amount of errors in ERC. But it looks that he placed at schematic symbols with lot of pins and not connected them what is obviously lot of errors.
Way of connecting capacitors to IC is not KiCad related so I will refrain from writing about it.
Thank you for providing a link to the Version 7 documentation.
While I have been using KiCad since Version 5 revisiting this is good for me too.
I at times despair of or have become a victim of trained helplessness when it comes to even finding the current documentation.
Advise for a beginner
As Piotr suggested work with the documentation at the link he provided.
Though it is for an older version, you can get an overview by a video tutorial of a very simple project at this YouTube:
Robert Feranec What is KiCad about? Starting with KiCad … https://youtu.be/maaBkw7IRUc
The reason is that when you go to www.kicad.org and then HELP-Getting Started the V7 version is opened what I didn’t noticed. When you select HELP-Documentation and then Getting Started the V8 is opened.
Looking over this thread, my recommendation would be to get on YouTube and watch some videos on using KiCad. There are really 1000s of them to choose from, but something introductory on KiCad, maybe including STM32 would probably be very helpful to you, @MariaInSpace
“Phil’s Lab” is a nice channel and has some getting started with STM32 in KiCad videos.
I can understand the difficulties you’re having - for someone new to this whole EDA thing it’s a complex topic to begin with, and learning the idiosyncrasies of a new (and complex) software package at the same time is a steep learning curve indeed.
I have never watched any YouTube KiCad video but I have seen many times beginners asking at forum why they don’t see in menu what they see in YouTube video. I think there is no way to delete from YouTube all videos for previous KiCad versions.
Yeah, you’re right, outdated documentation, whether on YouTube, Blogs, or official docs is always a big problem for support.
It’s especially bad around the release time of major versions, and that’s also an especially difficult time for new users to jump on-board.
But that’s something users (of any software) just have to deal with in the end. And if you’re completely new to KiCad and EDA, the basic principles do carry over across versions, and you will still learn a lot from a KiCad 6 Video I think.
And for conveying basic principles and giving people an “intro” to a GUI based application I do think video is a better format than long html pages with screenshots. But I appreciate each person’s learning style may be different, so feel free to disagree with me 
I think your advice and reasoning are sound 
From a complete beginners perspective anything is a ‘leg up’ and youtube is a valuable resource 
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