How to add project translation in Xcode?

Question

macOS

There is a small project in Xcode 10.1. You need to add a translation. The project actually consists of one .m file, there are no .xib or .storyboard files. Strings to be translated are wrapped in NSLocalizedStringFromTableInBundle. I read the documentation from Apple, but I don’t understand how to apply it to my case. In general, how to add support for a second language to the project? Only translation of certain phrases is needed. The application language selection should happen automatically when the application starts.