Preparation for ZCO

I am a beginner in competitive programming. Though I don’t know the C++ language much but I try solving problems using C++ and fill in the gaps by reading about some topics that come in the way of solving different problems. Recently I have been involved in solving the past ZCO problems so I wanted to ask if solving the ZCO problems is enough for the upcoming ZCO (2021)? Considering the time I have for ZCO (keeping in mind the time spent in school and other things) will it be advisable to go through graph theory as I couldn’t find any problems related to it in the past ZCO problems? And will Dynamic Programming alone suffice for ZCO 2021?