When you consult with the lawyer, the lawyer will explain everything.
Not a few word answer
Many experienced criminal defense attorneys offer an initial consultation at no cost. You should contact an experienced defense attorney who practices in the jurisdiction where the charges are pending. The attorney can discuss the strengths and weaknesses of the case and help the client make an informed, intelligent decision as to whether he/she wants to go to trial or cut a deal. A competent defense attorney should then be able to proceed according to the client's choice and negotiate terms of a plea agreement. In some cases, the prosecutor will not agree to any terms; the client can still plea guilty but will need to have a sentencing hearing for the judge to decide on what sentence to impose.