There are a variety of resources available which will guide you through what to focus on and where extra work can be done.
Often this will be referred to as ‘additional readings’. This can significantly increase the “study hours”, but as a guide each university unit is 10 hour of study per week (lectures, tutorials, workshops and study).
This would mean that a full-time study load is equal to 40 hours per week. If you are aiming to do well during study then it is advisable to have a plan, balance your work/study/external commitments, and make sure that study isn’t an afterthought.