Ubuntu 18.04.3 to use windows games on AMD x64 build

Hi, I used to be a windows 7 desktop gamer. After I installed ubuntu 18.04.3 bionic on this desktop. my new selfbuild AMD pc, I installed PlayOnLinux, then Steam, and logged in to Steam for linux?, tried to install Project cars 2 from dvd-rom but I think this needs to be a direct download thru the Steam website or such. Although Project cars 2 is listed on my favourites. Updates needed for Steam linux runtime. I also have Burnout paradise on dvd. Which i used to play on win7 intel Quad core i5 Ati 7770HD.

And nothing happens. Does AMD x64 system with ubuntu 18.04.3 OS work along side Play on linux and Steam, and if it works can i use code on dvd case to play game with download Project Cars2

thanks in advance

PS i am new to ubuntu OS
Selvbuild recently
Ubuntu 18.04.3 x64
cpu. AMD razen5
mobo. Gigabyte GA-AB350 gaming 3
gpu. Radeon 4Gb RX550
PSU. Masterwatt Lite 600 -80plus
HP 22in HD screen
Alpine 64 pro heatsink cooler
internet. 2 bars of [6mb] Wifi from friend at present
Nova [bitfenix] midi tower
Windows gaming for free ?