Are you really sure a career in IT is something you want to pursue? The companies I've dealt with are typically looking for people who can solve problems, on their own, by doing the research needed to figure out what the computer is telling them, what that means in terms of the problem that needs to be resolved, and then resolve it. So far, you have demonstrated none of these skills.
What can you do?
1) Contact the contest moderators / sponsors and have them delete the unwanted data sets.
2) Look on the IBM web site at the IXCMIAPU utility and find how to code up a delete for your logstreams, code it, and execute it.
3) Use IDCAMS to delete the extra data sets (but you'll need to do research to find out the high level qualifier used before doing so).
4) Figure out if you can run your CICS region without bothering to redefine the logstreams.
5) Find a forum to whine on until somebody takes pity on you and gives you the solution so you won't have to learn anything.
Your choice.
You REALLY do not want to attempt to run your CICS region without LOGGER going -- that would be a LOT more trouble to go through than you would gain.