Some say it was just a local flood only in the middle east, but that is not what
the bible says. The whole earth was flooded just as the bible says, and
the evidence is everywhere.
Gen 7:19 And the waters prevailed exceedingly upon the earth; and all the
high hills, that were under the whole heaven, were covered. 20 Fifteen cubits
upward did the waters prevail; and the mountains were covered.
You can’t cover the mountains with water and have the valleys dry…
Also, if it was just a local flood, why didn’t Noah just move away? He had
over 100 years to build the ark. He could have just moved his family in
that amount of time.
People also ask: How did they take enough food for everything?
Remember the two times in Matthew 14 and 15 where Jesus fed thousands of people
with a few fish and loaves of bread? God can do anything and He simply
took care of it. No mystery or impossibility. If God weren't
involved, yes, it would have been impossible, but God is not limited like we
are, He is God.