How would someone who had childhood sexual abuse behave?

No universal answer: Some people do adjust normally to abuse, and may not show any unsual behaviors. Some have specific or sexual functioning problems, and others suffer more disruptive disorders in terms of mood stability, ptsd symptoms or develop maladaptive persoanlity traits or disorders. Care must be taken not to assume abuse from current behavior. Treatement by psychologists and/or psychiatricst can help.

In the extreme: I agree with my colleagues answer. I would add that some victims of sexual trauma can become phobic of health sexuality (e.g. I had a patient with a history of sexual abuse who could not have any sexual relationship with her husband). On the other extreme, victims of sexual abuse can become "hyper-sexual" meaning that they engage in extreme amount and/or type of sexual acting out that hurts them.

Varies Widely: Survivors of trauma, incl. Sexual abuse, behave in all sorts of ways. Whether or not their behavior reflects their trauma depends on how they coped with it - incl. The stories they told themselves about it, stories they may have told others about it, etc. These stories capture how they made sense of the trauma & the meaning they gave it. How they coped likely also reflected the support they had.