How to install and use Drush in my code base locally or on the platform?

Installing Drush for Drupal 8 and later is as easy as to run the following Composer command locally: When you install project like Drush locally that contain an executable file, adding the following to your .bashrc .zshrc for MAC/Linux or equivalent for Windows will help you to run it when you are in your root of your project. This will insure to run the Drush from your code. For running Drush on the platform you do not need to do any thing as long as you have pushed the your vendor/bin directory to the reposetory. Platform will launch the Drush from your vendor/bin.

Note: The executable files will be in the vendor/bin directory.