hy
i'm in a local network with internet .
i have 2 Pc in the same home one on linux and one on windows .
i want to give internet to the windows pc from the linux pc witch is connected to the network with an IP like this 192.168.0.99 .
i want also the admin to don't see the pc wich is on windows .
can someone please help
see you
and tanks

I can't explain you all the process step by step but I'll give you some advices where to look for.
First:

(WinPC)-----------------(LinuxPC)>>>>>>>>>>(the internet)

The WinPC ethernet interface must have an IP address in the same LinuxPC netmask (ex. 192.168.0.88). This must be already so, right?

After this, I assume you already can connect to the internet properly using Linux. Is it so?

At this point, what you need is iptables for doing IP masquerade. You can have all the info you need at www.netfilter.org or posting another question about a simple iptables script that does masquerade (better in the security forum).