Global proxy in Windows 10, how to configure using command line?

Question

Windows

Hello. For a long time I can not find a sensible answer to my question. Maybe I'm not right Google, but alas, there is no answer.
What do you need. There is a specific project for my own use. For which it is necessary that all computer traffic pass through a certain proxy, which, of course, I prescribe myself.
I found articles that talked about certain programs that will allow this business to be done without all sorts of troubles, but I don’t need this. Because you want to figure it out yourself. I also read all sorts of articles where it was proposed to change through the control panel and so on. Yes, I seem to be able to, but I have a private proxy and I need to enter a login and password to use it, but alas, I did not find where to do it.
Perhaps I just didn’t dig quite a bit and everything is simple here, but ... I will set the level of difficulty for this issue - difficult, so do not blame me.
( Optional ) There are two questions and one request.

1. Request. Post articles if you have them.
   
2. If it is possible to register a proxy through the "Control Panel", then is it possible to register a private proxy, or rather a login and password for it?
   
3. If it is possible to make the point above, then is it possible to implement it through the command line, so that in the future the program will do it for me, and not myself?
   

Answer 1

It’s easier to register a local intermediary proxy server once
and, if necessary, change the configuration for a redirected proxy, I
advise 3proxy - it can redirect traffic to all types of proxies with and without authorization and without
rebooting pick up a new configuration
(the creation of which can be automated)
What kind of project is this .net app?