You do know that the most well informed people (like active researchers in the field) are often the most pessimistic right? Like you hear on the media that “oh no we’re gonna pass 2º! I guess I won’t be able to ski as much”. But you go to a climate science conference and it’s “yeah… now that we can add more parameters and feedback loops into our models the chance of total extinction by 2100 is 99.99%. On the bright side, half of us expected it to be 100%. So kudos”.
Sadly there are not a lot of extra-biblical sources on Jesus and his life actually.
There is one, a single one. And it’s pretty bad. Josephus. He basically mentions “James, the brother of Jesus they call Christ”, in the middle of a text not about Jesus at all.