"I recently read a book that basically says most of the Bible is myth, having no archaeological support. Now I'm confused and don't know what to think."
It is unreasonable to expect that archaeology will *prove* every record of history recorded in the Bible (or in any other text for that matter). It is also intellectually dishonest to leap to the assumption that a written historical record is false simply because archaeology has not proven it. Of course, it is also foolish to assume that something is reliable simply because it was written long ago.
A person who only accepts what archaeology has verified is a person who is essentially in denial of all of human history. Even most of relatively recent U.S. history is not archaeologically provable. We rely on a written record of it. Are we to think that the only people who suffered violence at the hands of slave masters are those whose bodies have been preserved to allow us to see the evidences of abuse on their bones? Even this would not be archaeological proof. How do we know what caused those indications of violence they suffered, apart from the written historical record?  Consider forensic science: Even in modern times with advanced technology, forensic scientists are often unable to gather enough evidence to really know what happened at a crime scene, or even link the crime to a still living criminal. If modern forensic science can fall short of providing a clear picture of what happened in the recent past, sometimes only days before, why would ancient archaeology be any better? And this is pretty much what forensic science really is - archaeology for modern occurrences. Archaeology is basically forensic science for ancient events. If oral and written evidence are given serious consideration in a court of law to fill in the blanks where forensic science fell short, should not such the same be true for ancient history? All the more so! And when oral or written evidence seem to conflict with the results of forensic science in a court case, are oral and written testimony then entirely thrown out the window? No! An attempt is made to form conclusions taking into consideration the entire body of evidence, with an aim at coming to the most logically consistent conclusion. Very interesting that this approach is abandoned by anti-theist archaeologists when it comes to a record of history that entails moral liability. Just a thought.
Archaeology can only give us hints of glimpses into the past, but it falls terribly short of providing a clear or full picture of any historical event. The only tool we have for acquiring any clear picture of ancient history is the written record.  Does this mean it is impossible that a written record could be inadvertently in error despite the sincerity of the writer, or that a writer could even have intentionally fabricated or exaggerated an account? Of course this is a possibility. But to disregard a written record JUST because of this possibility is dishonest and irresponsible. Unless a person wants to live life as though history does not exist, he MUST accept written records as true, on certain conditions, despite the possibility of errors. It would be an even greater error not to do so.
In order to lessen the likelihood of being mislead by unreliable written records, one must form a logical approach whereby he can determine whether a written record is trustworthy or not. Any person's approach will be influenced to some extent by his personal assumptions. Those influential assumptions themselves may or may not be very logical. So what we must do is strive to develop our criteria for regarding a text reliable, based on assumptions that themselves are most reliable. It is my understanding that the most reliable assumption is that truth is consistent with itself, and contradiction indicates either falsehood or a lack of essential information. All this taken into account, my conclusion is that the Bible is a reliable historical record. The only reasons I can think of that a person might dispute this would be as follows:
1) pure unwillingness to be objective about the matter due to the implication that if the Bible is reliable, then he will be liable;
2) the assumption that extraordinary occurrences in the physical world are an impossibility;
3) the assumption that there is no Creator;
The first reason is a result of emotional immaturity and the intellectual dishonesty that it causes. The last two are a result of either a mental handicap, terrible ignorance, intellectual dishonesty due to emotional immaturity, or an irrational blind faith that contradicts everything observable in the physical word -- also due to intellectual dishonesty caused by emotional immaturity. What atheists fail to acknowledge is that atheism is an even less substantiable faith than ANY religion that acknowledges the Creator.
Hope this helped.
R' Yosef Eliyah
 Oral tradition is also a source of knowledge. But written records have often survived longer than oral traditions, usually provide much more detail than oral traditions, and are usually less corrupted than oral traditions. Note the words "often" and "usually." Exceptions can exist. The main point is that archaeology is inadequate for providing us any substantial knowledge of history. It can be used to support a historical record or give indications of events that were not preserved in writing, but it would be very difficult, if not impossible, for archaeology to disprove a historical event, especially when the results of dating methods can sometimes vary greatly from test to test or from method to method, even when not giving consideration to chemical variables we're unaware of that may have occurred to the archaeological find.