What am I Supposed to think about

I've been meditating for a week and largely i see no benifit to it and i think its because im not thinking of it correctly or im doing something wrong

The question i have is when i meditate should i let my mind wander, let it find thoughts and think those thoughts through until i come to a conclusion, for example letting my mind wander to ideas of morality or ethics or how i should study or my relationships. or is the purpose of the meditation to be mindless or try and focus on "nothing" or something close to nothing (like my breathing) to clear the mind, Be in the present moment and let all other concerns and ideas completely fade away.