Hi. Welcome to the forums.
Searching Google for HP touch smart 23-f213 finds a lot of links. You can check specs and reviews for the machine as well as discussions of problems, current prices and much more.
It sounds like you don't know a lot about computers. If so, when buying a used machine, especially one without a hard drive, either you really need to know what you're getting and what it will take to restore it, or you have a good personal friend who does.
You'll also have to buy a hard drive so add that to your actual cost.
To install Windows, you will need an OEM copy of the version of Windows that came with the machine. You can probably borrow a copy because the license to install it is built into the machine. You'll also need to know how to do this or someone who does.
There's a lot more, and you'll need to know how to do these things or someone who does.
Tell us more about what you already know, and we may be able to provide more help.
