how to install apt-cyg for Cygwin?

taken form here - explaining how to install apt-cyg

Install apt-cyg

You may have heard of programs like apt-get (Ubuntu), yum/dnf (Fedora), pacman (Arch), or brew (Mac OS X)... .. .The analogous program for Cygwin is called apt-cyg.

Installing apt-cyg is simple. First, save this file: https://raw.githubusercontent.com/transcode-open/apt-cyg/master/apt-cyg . Then, use File Explorer to find the file in your Downloads folder and move it into C:\cygwin\bin. Then, open Cygwin and enter "chmod +x /bin/apt-cyg". This tells Cygwin that you want to be able to execute the apt-cyg command. Lastly, enter "apt-cyg mirror ftp://sourceware.org/pub/cygwin". This sets up apt-cyg to use the official repository when downloading programs.

Sounds simple enough. But i have an error.

This tutorial does not specify with what name and what extension to save that file.

I save it as apt-cyg.txt, and move it into C:\cygwin64\bin

This does not work. When running apt-cyg, I get the error: bad interpreter: No such file or directory

My guess is that extension or filenames are bad. What name and extension should i use?

Are there any more steps to this process?

Note: I just installed cygwin on a windows 10. Please don't assume i have other tools already installed.

Remember that the setup-x86.exe or setup-x86_64.exe downloaded from https://www.cygwin.com/ is the official method for installing cygwin. If you install using some other method and have problems, you may get little or no official support. Just use the official gui installer to install and update packages.