This is one of several questions in this tournament focused on nuclear proliferation, force sizes, or yields. See here for a list of such questions and some discussion of these topics.
"The Treaty on the Non-Proliferation of Nuclear Weapons (Non-Proliferation Treaty, NPT) is regarded as the cornerstone of the global nuclear non-proliferation regime and an essential foundation for the pursuit of nuclear disarmament. It was designed to prevent the spread of nuclear weapons, to further the goals of nuclear disarmament and general and complete disarmament, and to promote cooperation in the peaceful uses of nuclear energy. A total of 191 States have joined the Treaty, including the five nuclear-weapon states."
Four states—India, Israel, Pakistan, and South Sudan—have never signed the treaty. In addition, North Korea (a signatory since 1985) withdrew from the treaty in 2003. India and Pakistan possess nuclear weapons, as does Israel (though they do not admit so publicly).
Will these countries join the nuclear Non-Proliferation Treaty before 2024?
This sub-questions below will resolve as Yes if, between January 1, 2021 to January 1, 2024, the respective country joins (accedes to) the NPT, according to its depositary governments (USA, UK, Russia), as reported on the UN website, official websites of the depositary governments or by reputable new sources.
For the sub-question "India, Israel, or Pakistan", any one or all of those 3 states joining the NPT will be sufficient to resolve the question as Yes. For "South Sudan", only South Sudan's accession to the NPT is necessary to resolve the sub-question as Yes.