A dead person and a teacher may refer to a kind of growth in your subconscious. The death of your potential teacher means a new life-your growth. You don't need this teacher anymore. His death symbolizes your growth and maturity.
Catching fish in this dream may mean harvesting! Moreover, the water is very clear, and catching fish (fishing) with dad in the clear water shows that you can be independent, or to some extent, you can succeed in the same position as dad!
Holding a memorial service may be that the subconscious is still missing the experience of having a teacher, so crying in a dream prompts: accepting the fact of growing up is a good thing, and the subconscious prompts you to move forward!
Good luck!