There is no way to learn Windows by assuming it's like Linux, that's like learning to drive a truck by pretending it's a toaster oven. Give that idea up now.
Windows isn't Linux and what you know about Linux isn't going to help you administer windows.
That being said, if you prefer a command line interface to using a GUI, you now have an excellent choice for Windows administration; Learn the PowerShell. It is inspired by the design of the Unix shell and unix tools, but it uses some different core concepts. Where "everything is a file" is a common Unix trait, that is not true in Windows. PowerShell lets you walk around the Registry and WMI and other things that are not anything like a file system with the same kind of ease that you are used to walking around in filesystems, but you must be aware of the differences.
The /home/twyderka folder on Linux is probably c:\users\twyderka in Windows, at least in Windows vista and later versions, but that's not true on Windows XP or Server 2003. It used to be called C:\Documents and Settings. As far as /usr/bin, you could say that's similar to C:\Program Files, but on some international versions of Windows those paths are different. You can use Environment Variables when scripting, to find things like the user's home directory, not hard coded path names.
Forget all about "package management". Windows doesn't work like Debian Linux and there is no replacement utility for Apt-Get or RPM. There are command-line ways to install packages, which are often ".msi" files, but those installer packages work by very different rules than the package systems on LInux.
Administration of Windows Servers requires about a book-shelf of over 10K pages worth of books, if you are expected to Administer a domain controller, file server, and all the rest, but if you are simply "administering" a windows client Desktop machine, you just need to learn how to solve common problems in Windows, and install updates, and so on. Since you haven't even said what "administer" means, we'll assume you mean fix it when it breaks. Here's my advanced admin school for Windows client PCs:
- See error message.
- google error message.
- Try stuff that was in the pages you got from google.
- Rinse, repeat.