The conceptual framework describes how you came up with what you did, what you did, and why. There are a number of ways of describing this.
Often people draw out a flow diagram as a methods to describe their conceptual framework.
Like this one drawn here (its a bit complicated but hopefully shows the general idea) http://www.icbl.hw.ac.uk/ltdi/implementing-it/frame.htm
If you were to draw a process diagram of the conceptul framework for your projects about leeches and anaestheisa you might put boxes at the top for the different topics in your background research like leeches, anaesthesia and nerves, then the different aspects of your research question as boxes and then the arrows to how you will address those questions.
Or you can do it all in text. Starting with each idea and then discussing how you formed the idea into the question, how you will test it and then what you found.
Maybe you could talk to your teacher about what they expect for you to do as they might have a specific idea about how to format it.
Best of luck,