0. in terminal:
composer global status // this will get composer Directory

1. in terminal type:
nano .bash_profile

2. then insert into file:
PATH=$PATH:$HOME/bin:/home/andrey/.composer/vendor/bin
export PATH

3. then safe file

4. every time to start in terminal type:
source ~/.bash_profile  // Now you are able to use Codeception anywhere in your system

5. then in terminal type ti use:
codecept