According to Imam Hamza Yusuf there are a number of areas of which one should study their Deen and in a certain order. It is not an obligation for everyone to become a scholar, or in fact to have knowledge of every matter. For example, you are not required to know the laws of marriage unless or until the moment that you are considering marriage. Now that does not mean, right before or after you are married; but if you have no intentions of getting married it is not required for you to have knowledge on the Fiqh of marriage.
The areas that he states and in this order are:
Aqeeda- the basis of our belief and faith as Muslims
Fiqh- Islamic law in various subject areas. ie. worship, marriage, business
Akhlaq- Virtues and Manners, ie., purification of the heart, good company, etc