what's going to happen if i say "plead guilty"? what does it mean if I say that?
If you enter a guilty plea, you are giving up your right to have the case resolved in a way that will keep it from remaining on your permanent criminal history. I do not recommend you enter a guilty plea, but instead, either hire a lawyer or ask that a public defender be appointed. A lawyer can determine if you qualify for a bad check diversion program that would allow you to repay the money owed and earn a dismissal of the charges. This is a crime of dishonesty and can adversely effect your job opportunities in the future, so it's not a good idea to simple enter a plea.
Posting an answer to your question does not create an attorney / client relationship such that you can or should rely on the information provided herein to take action. Instead, it is intended to simply provide you with information. I am not your lawyer and cannot provide you with legal advice unless and until I am hired to do so.
Criminal Defense Attorney
Sometimes you can just let the state know that you wish the pay off the check and they will either reduce the charge, drop the charge, or withhold adjudication. Most of that depends on your criminal history. If you have actual defenses to the charge and definitely want to fight it, hire a private attorney or a PD.