Creationism as it is usually understood and accepted is a belief in a young earth, Genesis taken literally as is the rest of the Bible.  It accepts a world wide flood, and all the accounts of the Bible are historical and scientific...see Ken Ham and Answers in Genesis.  The problem is there is no evidence at all to support any of it, but considerable evidence refuting it.  The questions which ought to be begged;  Is it pointless to believe in something without proof, Can we honestly call it, or anything truth, if we cannot show that it is true.  Truth is that which is concordant with reality.  Creationism totally falls apart, as does the Fall (see above) with the non historical fable of Adam and Eve and thus Original Sin.