No ProBuilder in Package Manager [HELP!]

So, recently I installed unity and I started to make a simple game. So after a couple of minutes of playing in unity I noticed that there is no ProBuilder in the package manager. I was confused and I went to google it to see if there was any solutions. I came across some that I tried but didn't work. So can anyone please help me. Thank you in advance.

 

Did you follow the instructions here? https://docs.unity3d.com/Packages/com.unity.probuilder@4.0/manual/installing.html

 

from Brackeys "To those of you who can't find the package: Unity has moved the "Show Preview Packages". You can now find it under Edit -> Project Settings -> Package Manager -> Enable Preview Packages. If you check that box, you should see preview packages in the Package Manager! : - )"
Also at the upper left corner of package manager sort by "Packages: unity registry"