i think before you want a port to be stealthed, you need to understand what it means
"open" means there is a server running on your computer, waiting for connections on that port from the internet so it can serve them (on a web server, port 80 will be open.) "closed" means there is no program listening on that port, and nobody can connect to it. "stealth" is just a made-up word that means when they tested that port, they didn't get any response back at all. "stealth" is only useful if all of your ports are that way, which they usually aren't because ports need to be forwarded for a lot of things to work (like file transfers and bittorrent.) if any of your ports are open, even if you want them to be, it defeats the point of having any ports "stealth," which is only to prevent people from checking whether your IP belongs to a real computer or not.
Also, if you're using a router or certain kinds of modems, it will make all ports appear "stealth" except for those you have "forwarded" to a certain computer in the router/modem's config.
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