Handling difficult questions. It is important not to start responding to a difficult question before you have thought about the answer. Repeating the question and asking for clarification will help create some space for your thoughts.
Make sure all loads in vehicle are turned off, key is in the off position. Disconnect the negative battery terminal first then the positive terminal. When installing the new battery connect the positive terminal make sure not ground out the tool your using while tightening the positive terminal.
If yes, you see corrosion, then you've got work to do. Remove both battery terminals with a socket wrench. Make sure you remove the NEGATIVE (black) cable first. Please watch what you're doing here. Don't short circuit the red terminal to any metal part of the engine or your going to be sorry. Just be cool when you ratchet the wrench back and forth.