You are part way there.
Click the online tab.
In there you will see Updated on the right.
Click that.
Install those that show up.
When finished, click on settings.
Then top right AIGAIM-OCI
On the bottom row of that screen click verify setup.
After done, you have the AIG Manager set up.
To use AIG, after you have MSFS running with your flightplan loaded, start the AIG Traffic Controller.
You should have lots of AI with the correct airlines at the proper airports.
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