@rrekih 

Hi,

Does your network only consist of computers and Powerline adapters? Or is there also a router connected to this network?

If there is a router connected to your network, then you normally don't need to do anything special to "network" everything together. As long as the computers are configured to obtain IP addresses automatically via DHCP the router should handle everything that is needed and also the Powerline adapters will configure themselves based on the DHCP information they receive from the router.

  @woozle

I have the network that comes into the house, it supplys internet and TV.

There is a Modem that the TP-Link ties into.

  @rrekih 

So you already have some devices (like TV, smartphones) connected to your home network and they can access the Internet, right?

Are the two computers that are connected to the one TL-PA9020P also able to connect to the Internet?

  @woozle 

Yes I already have TV and smart phones connected to the internet.

the TL-PA9020P has access to the internet as well.

I was able to select a folder and share with the other computer but I had to select "everone"

Im not able to see the other computer name to share with just it.

  @rrekih 

Have you activated Network Discovery on both computers? What happens if you click on "Network" in the Windows File Explorer? Do you see the other computer? In case you get a message about Network Discovery being turned off, then you need to turn it on first. (also refer to the pictures I added below)

Do your Windows computers have passwords set up? In case you need to enter a password in order to log into Windows, then you should be able to connect to folders of the other computer by entering the username and password of that other computer when asked. If your Windows doesn't have a password set up, then you need to set one.

  @woozle 

I have 2 computers called PC1 and PC2

On PC1 i can see what I share on PC2 but not the other way.

also under network I don't see both computers listed.

On PC1 under network I see PC2 and under that the folder that I shared on PC2.

  @rrekih 

Make sure that your Ethernet connection is set as "Private network" and verify "Network discovery" and "File and printer sharing" are on, like shown in the screenshots below.

  @woozle 

Yes all set up like that.

When I go on PC1, Network I see PC2 and what I have shared.

On PC2, Network I see PC2/Users/Owner & public. Not PC1 though.