There are many ways to prove the authencity of a history
document which the bible is, and these are the basic methods to
authenticate history that we know of nowadays like, which emperor
ruled the which empire in china etc....
Internal evidence - meaning does the document contradict
itself.
For this, the bible does not contradict itself despite being
written by 40 over writers over a span of 1600 years. Supposed
contradictions brought up were all refuted because it was taken out
of context.
External evidence - are there any other documents supporting
it?
Apparently, events described in the bible were not exclusively
found in the bible but even in writings of Socrates and Josephus
and others.
Archaelogical evidence - things like dead sea scrolls were found
and other archaelogical evidence points to authenticity of events
described in the bible.
I have all these studies on paper but too long to write here
hehehehe. If you wan, i can pass u a copy somehow.
HOWEVER, i must say that despite such evidences that the bible is
real, I am of the great belief that FAITH is more important that
all these what our eyes can see. It is what I experience after I
became a christian rather than all these evidences that make me
trust in God more.