How to exchange packages with a mobile online android game server?

Question

Android

Good day!
There is one mobile online game in which I automated one process, through bluestack and auto hotkey and keyboard according to the picture.
But I realized that this is still a crutch and decided to dig deeper. After reading the materiel, I realized that the server is exchanging packets with the client. I want to make a program / bot that / that will receive packets and filter out those in which the given condition does not match.
Let's say players sell their goods in a chat, following the logic, then you can guess that a package has come to me, which indicates what kind of product it is, what kind of player wrote in the chat, etc. I cut off the packages that I need and when I have received the packages that I need, I send another package that sends a request to the server to "leave a message in the chat" or "write the seller in private messages" (I already received these packages in advance ).
Hence the questions:
1. Where to start studying information or materiel?
2. On what it can be implemented? So that I can do this in the tray through the bluestack or some third-party software.
3. How to make a trigger on a packet to filter it out?
From myself, I’ll also say that I looked and tried to do everything through a sniffer, such as Wireshark. Through Charley, but everything is somehow tight ... They only helped me to receive and send packets, but how can I do it all by trigger?
Thanks for reading to the end. Correct me if I'm wrong somewhere.

Answer 1

1. From learning how PCs and networks work at all levels, then continuing with the study of programming and software development, then gaining tangible experience in software development on the same platform on which the game is launched, then reverse engineering the game, as well as its mechanisms for working with the server .
   
2. Anything that can send data over the network.
   
3. According to the user manual for the instrument in which the trigger is located.