How to work with subproject tasks in MS Project 2015 from the main project?

Question

Project management

Good afternoon!
In MS Project 2015, I add subprojects to the main project (as separate project files), they have tasks. why can't I edit subproject tasks from the main project? After all, these subprojects are part of the main one. Or am I wrong?
Is there any approach to such problems?
When trying to move a subproject task from the main project, the following warning appears:

Answer 1

You can move tasks only within one subproject (source file), i.e. the task cannot be transferred to the parent project or to the neighboring subproject, but it can be copied.