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.
I would just touch the negative cable to the battery first to make sure everythings hooked up correctly. When connecting your battery, connect the positive (red) first and the negative (black) second. When removing the battery, disconnect the negative (black) first and the positive (red) second. Been doing this for nearly 30 years. ALWAYS connect the positive post first.