To summarize:

Ther are also other components that helps a website run smoothly.

used when a website traffic is high or the website need to be high available.
A load balancer receives the request and forward to one of the many servers behind it.
It uses different algorithm to help it decide which server is best to deal with the request.
example are round-robin (give request to servers in an order). or Weighted which checks how many request a server is dealing at the time.
They also periodically check the servers are running correctly. this is called health check.
If a server doesn't respond appropriately or doesn't respond, the load balancer will stop sending traffic until it responds appropriately again.

How Web servers work?

is a software that listens for requests and utilizes the HTTP protocol to deliver web contents to it’s clients.
The most common such software is Apache, Nginx, IIS and NodeJS.
A webserver delivers files from its root directory
for example /var/www/html/picture.png from it’s local hard drive.

Web servers can host multiple website with different domai names. They use virtual hosts for this purpose.
Virtual Host are just text based configurations.
Virtual Host have mapped their root directory in different locations of the hardware.
For example, one.com being mapped to /var/www/website_one, and two.com being mapped to /var/www/website_two
There is no limit to the number of website that you can host on the server.

Static Contents are that never changes.
Common examples are pictures , JavaScript ,CSS and can also include HTML.
Furthermore, these are files that are directly served from the webserver with no changes made to them
Dynamic Content on the other hand are the content that could change with each request.
example would be a search page which changes content based on the search text.
These changes to what you end up seeing are done in what is called the Backend with the use of programming and scripting languages