What is Islam's ruling on one who does not believe in the Last Day and the Resurrection, and is he considered a disbeliever, and what is the best way to deal with him?

Whoever does not believe in the Last Day or the Resurrection is in the greatest degree of disbelief. Belief in the Last Day is coupled with belief in Allah. The connection between belief in Allah and the Last Day has been mentioned in many verses of the Holy Quran and the Prophet's Sunnah. Such a person is treated like other disbelievers: he is invited to Islam and to repent from polytheism. If he does not respond, then it is obligatory to keep away from him.