Main menu go to training ground
Here you are teamed up with bots agents a team of bots and have to complete 5 scenarios.
The scenarios are The Basics (Warzone with Execution rules) (Execution with Respawning) (Guardian Objective) (Annex) and Submission.
Also, stay until the countdown on the top of the screen reaches ZERO. Do not press pause and exit like the screen prompts you to, otherwise you will not get credit for completing that stage.
That's it 10g is yours
As you can see I haven't done it yet but have played GOW 2 and have done it there