I'm programming on objective-c. I've removed all files from MyTarget -> Build Phases -> Copy Bundle resources. How can I return it because my project doesn't work?
You need to add them again. If your project structure is good then you should have them in the Resources folder. If not, it's a great time to fix your project structure, but unfortunately you will have to add every single resource file manually.
Also, as SDK is shipped with git nowadays, it's good to use it and commit your changes. If you used git, reverting this would be as easy as reverting the project file to the previous version.