I've need to install a software (NetOpSchool Software and a Antivirus) and I have a server client based set of computers which is connected. I want to know how to install a software from the server other than installing it one by one in the client machines.
There are readily available automated software deployment tools. In your panic you have neglected to tell us what platform you're using but as NetOp School appears to support only Windows (unlike some of their other products) I guess you want a Windows tool. Have a look at WPKG.