A few things… Paul while he doesn’t talk about Jesus directly as much as the Gospels, which are more an account of his life - rather then a theological narrative that Paul does… He paraphrases the Old Testament like mad such as Micah, Isaiah 40, etc - in pointing to who Jesus is… which is God/Messiah.
This is important to understand because we forget the apostles were not as fixated on writing down everything immediately after Jesus’s life, but it only occurs slightly before and after the Jewish Temple - They are actively using the Old Testament (Hebrew Scriptures) to claim Jesus as Messiah. We forget there was no New Testament in their time. It wasn’t like the Galatians were busy also reading the letter to the Romans. That by all accounts happens at the earliest around 80-100 years after Jesus’s death.
A great book to read is called Jesus and the eyewitnesses. One of the best points this makes is for example how preposterous it would have been for Jew’s to write that women were the first witnesses to the resurrection if this was a completely fabricated story. We see this from a 21st century lens and think no big deal. This was a time period where 99% of the world considered women slightly above an OX in terms of pecking order. They were not allowed to testify in a court of law, etc. They were legally considered property in most of the known world. Why would you write apostles loyal for 3 years… all bailed but one… if it didn’t happen. Why would the eventual writers be so clear how pathetic they were when the rubber met the road? If it wasn’t actually true.
Another point is Paul’s letters, the Gospels, etc cite minor players by their FULL names. So for example… yeah you might had read Mark’s Gospel 30 years after the death of Christ… but the people named or at least the family members of those people named were still alive. So you want to hear about Lazarus? Well even if he wasn’t still alive… someone who knew him would have been. Go to that cities small Christian community, someone should be there. Paul’s writing everyone he can in the known world? Well he mentions tons of people he personally knows by name as well. They would be still in those churches or their direct descendants. Completely available to people. You never hear Jews write such a counter text for example. Which compare that to lets say Mormon’s where you have libraries full of text written immediately after or shortly after the claims of Joseph Smith… Heck the internet itself is teeming with it. The LDS don’t even know how to handle the problem this readily available church history creates. Why did Jews never provide the rebuttal?
Another quick point… Still today there is a cult in Syria (and surrounding areas) who believes John the Baptist was the actual Messiah (wikipedia it). There are 100’s of thousands of followers of this religion (too lazy to get the name). So John the Baptist is a pretty important hombre… actually the Bible itself basically states he was the best of men ever born. His legacy is still so strong enough people worldwide the size of a city like Reno or Spokane today believe he was actually the messiah. If the apostles are busy linking Jesus and John the Baptist… why didn’t this cult, or John the Baptist followers of that day shut it down? Heck you can read in scripture that it’s plausible John had a bigger following than Jesus did in their respective lifetimes.
My point is this… to argue Jesus wasn’t even a historical figure is pathetic when compared to the certainty we have that Caeser, Cleopatra, Plato, Aristotle, Alexander the Great, Ramses, etc were alive. Respectively there are far more text snip its of the early New Testament (about 6000 pieces if I recall) that don’t show edits and don’t contradict each other (even if they are just small fragments - that compared to some of the people I listed above… Jesus has a wealth of writing… Most of the people above don’t even have a 100 text snip its to their name. But there is no doubt of them actually having graced this planet.
The second something is history and in the past… it has to be taken by faith… no matter if you’re talking about Lee and Grant fighting in some civil war none of us were alive to see or Jesus.
Now if you want to argue that shakesphere didn’t really write most or many of his plays… now that’s a better argument all together.