If ganache is too soft,can it be remelted and add more chocolate to it, and if its too hard can it be remelted and add more heavy cream to it? Just wondering because I'm about to make a batch for the first time. I guess I'm  lacking in confidence.

Yes, you can add more cream to it to make it softer. Write down notes of what your original recipe was and how you adjusted it, for use in the future. Good luck!

Thanks