There isn’t, like, a whole lot of evidence for Jesus’s life, but there is at least as much as is reasonable, given the context a person like him was living in. You’re not gonna get much about what his life is like that isn’t in the Bible.

Historians are adamant that he existed, though. The FAQ has a section on how we know that, which involves analyzing not only the contents of the sources at the time (Biblical or not) but also how they were actually composed.