My basic idea about a small website or LANsite(a simulation of website) and how to implement it

I tried analyzing what in essence is a website . I came to the conclusion that :

" A website is basically , a computer program , which in response to a signal from a remotely located computer , executes some program stored in it and depending on the outcome of these program ,sends back some signal to the sender computer system "

All the websites , I have seen till date , have been graphical but I guess the first systems might be like , one computer having a terminal, where some commands transmit some signal to another computer , which on receiving these signals performs some computation and sends back some signals .

My understanding is that , when a website name is typed , the browser sends signals to the domain , the domain sends back some signals ,out of which the browser makes an HTML page , which it uses to graphically arrange the contents and sites of event (this term I am using to mean controls like buttons or drop-downs). Then when the user clicks or swipes or anything , the browser sends the signals in response to the generated event to the domain , where the signal is processed and according to the identification of the signal some program is executed and some values are signalled back to the sending system . The browser in the sending system then on the basis of these signals modify the html contents and give some result to the user using the browser or maybe provides a new graphical rearrangement of the existing stuffs .

I wanted to know if this understanding of mine is correct or not .

Now if it is correct , I would like to simulate a website on my own PC. What I want is I will have a folder where I will be having some programs stored , like some perl or python scripts and some images or some articles etc .In a notepad , I will be having a simple html stored , which I will launch through my web browser . Now I will generate some event whose information my browser will transfer to my own system and the scripts in my MAGICAL folder will get executed and depending on their output something will be sent to the web browser and the browser will edit the html notepad file and launch it back .

Will this be eligible to be termed as a simulation of a website ?

The following are the things in which I need the know-hows :

1. How will my browser transfer the event about the mouse click to my system ?

2. How will my system receive this information ?

3. How will the output of the scripts be sent to my browser ?

4. How will my browser edit the contents of the html notepad file on receiving the signal ?

Basically , I think, if I am not wrong , for the last part sometimes the domain on being contacted sends some javascript(or anything that can dynamically edit an html file) programs for the browser to place locally .(I think this what it means when my browser while opening some page writes "downloading scripts" )..

So , is my understanding of a website correct and how can I answer the gaps I have in my simulation of a website ?