How structure a engine for multiple projects

Hello Team. I am a beginner in github, but i do understand this. Example:

I have 1 (Main Engine) on localhost. This engine is a cms. Now i push this engine to my github repository.

For the next step i create a plugin on my localhost.

Its (Main Engine + Plugin A).

After that (Main Engine + Plugin B).

Now i can make a brunch and push (Engine+Plugin A) to github. Same with (Engine+Plugin B).

The problem is, when i update the only (Main Engine): The other versions doesnt have this update :frowning:

How i must structure this example? Many thanks :slight_smile: