Muhammad ibn Abdullah (peace be upon him) is their seal, as Allah (may He be Praised) states:
And verily, We have sent among every Ummah (community, nation) a Messenger (proclaiming): "Worship Allâh (Alone), and avoid (or keep away from) Tâghût (all false deities i.e. do not worship Tâghût besides Allâh)."
Messengers as bearers of good news as well as of warning in order that mankind should have no plea against Allâh after the (coming of) Messengers.
Muhammad (ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭﺳﻠﻢ) is not the father of any of your men, but he is the Messenger of Allâh and the last (end) of the Prophets.
Every Muslim has to believe in the messengers that Allah named or authentically mentioned by the Prophet in his Hadith. Among these messengers are Nuh (Noah), Hud (Eber), Salih (Shaloh), Ibrahim (Abraham) and many others (Peace and blessings of Allah be upon them, their families and followers)!
As for belief in the Last Day, which entails belief in all the events that will happen after death and are affirmed by Allah and His Messenger (peace be upon him). Among these events are Fitnah (trial) and the torment or joy in the grave and the events that will occur on the Day of Resurrection, such as the reckoning, punishment and reward, the Scale, Sirat (the bridge over the Fire), the phenomenon when the pages are made public and one will be given his record in the right hand, the left hand or behind his back. It entails also belief in the Hawd (Prophet's lake in Paradise), Paradise, Hellfire, the believers' seeing and speaking to Allah (may He be Praised) and the other things mentioned in the Qur'an and Sunnah. Every Muslim has to believe in all these things as taught by Allah and His Messenger (peace be upon him).