1. Motherboard

What do you need to make a computer?

First you need to have a motherboard that is the most unwieldy component in your system, but since it acts as the foundation for everything else in your case, installing it correctly is of paramount importance.

The motherboard also determines what other pieces of hardware the computer can use. 

It’s the highway they use to communicate and collaborate. They come in different sizes and configurations, and each one looks a little different, but they all fill the same function

Normally when you have to say the computer components always start with the motherboard, because it is the primary circuit board that holds all the hardware in place

When a motherboard is damaged, PCs cease to function fully. Noting the complexity of the circuitry and wiring in place, a faulty motherboard can instantly stop your computer from working and potentially harm other parts. While motherboards are easily replaced for desktops, the same can’t be said for laptops, forcing you to buy a brand new one.

How can I install a motherboard?

With 4 steps you can install one: 

https://www.digitaltrends.com/computing/how-to-build-a-pc/

And there are some webs to buy one:

https://www.newegg.com/Motherboards/Category/ID-20

https://www.microcenter.com/site/products/motherboards.aspx

https://store.ee.co.uk/category/processors/11022

Explanation of motherboard:

They can cost between $50 and $1000