Update README.md

Author: tinawebdev

07-blackjack/README.md

@@ -1,15 +1,25 @@
 # Blackjack
 
-## To use the code
+## Install G++ Compiler
+The g++ compiler is a free, open source compiler available on almost any operating system. g++ is part of the [GNU Compiler Collection](https://en.wikipedia.org/wiki/GNU_Compiler_Collection).
+
+### Windows
+If you are running under the windows OS then I recommend you download: [MinGW-w64](http://mingw-w64.org/)
+
+### macOS
+Just go to a terminal and type `g++` and it should offer to install
+
+### Ubuntu
+```bash
+sudo apt install g++
+```
+
+## Install Game
 * Open Terminal and change the current working directory to the location where you want the cloned directory to be made.
 * Download the repository using the [instruction](https://help.github.com/en/github/creating-cloning-and-archiving-repositories/cloning-a-repository).
 * In the command line go to the directory with the files downloaded:
 ```bash
 cd cpp-games/07-blackjack
-```
-
-**How to compile game using GCC C++ compiler (g++)**
-```bash
 g++ -o game -I ./lib *.cpp lib/*.cpp
 ./game
 ```