Thank you for your answer ASHLEY. I didn't know there wasn't enough information to help with the topic. Fixing it :)
1. I want to buy Facebook ads for my app. In order for Facebook to detect application settings, I need to add the Facebook plugin to my application in C3 and create a new project in my Facebook account. I did it (1st screenshot).
2. In order to complete the project setup in my Facebook account, I also need to provide them with the hash-key of my keystore.jks (I did it) and specify the main active Facebook plugin/sdk class. I entered this field at random, but judging by the fact that Facebook does not track installations of my application, I did it incorrectly (2nd screenshot).
I need help providing Facebook with the tech information it needs to be able to track my app installs. If you need any more information, I'm happy to provide it.