There are several facts about Jesus' life and ministry that the vast majority of New Testament scholars and historians accept as truth. Of course there are a couple of wildcards that don't accept them, but there are always gonna be those kind of guys who aren't willing to accept stuff even if it's indisputable.
Here's a rundown of the things we know for certain about Jesus:
1) Jesus lived. Born around 4BC and died around 33AD (give or take a few years).
2) Jesus was from Nazareth.
3) Jesus was baptised by John the Baptist.
4) Jesus was a great moral teacher.
5) Jesus preached radical new ideas.
6) Jesus had several disciples.
7) Jesus had a reputation as a healer and exorcist.
8)
Jesus was beaten and crucified to death for blasphemy (claiming to be
God/God's son) by the request of the Sanhedrin under the orders of
Pontius Pilate.
9) Jesus was buried in a tomb by Joseph of Arimethea - a sympathetic member of the Sanhedrin.
10) Jesus' tomb was found empty by some female disciples.
11) Jesus' disciples claimed and truly believed to have seen him risen from the dead.
12) Creeds referring to Death, Deity, & Resurrection can be dated to within the same year as the crucifixion.
13) Christianity spread quickly.
14) Several of the first disciples/apostles were martyred for refusing to denounce Christ.
Considering all these taken together, there is no explanation that makes sense of it all except that the story of Jesus as presented in the New Testament is true.