So you are doing an essay on how to write an essay, prepare for a debate, make a speech, and conduct research? Phew! That is enough for four different essays.
I guess what you should do for any of these is to first research whatever topic you are dealing with if you dont have enough information already. After looking over all of your research form an opinion about whatever the issue is you are dealing with. Then find examples in your research to back up your opinion.
For instance if you are doing an essay on a piece of literature then your research would be to read the book. Then you take a stance of whatever the issue you want to deal with is. Then you would find quotes and examples from the text to back up your stance. Your stance should be summarized into a thesis statement at the begining of the essay and dont forget to include the answer to the "why" question concerning your stance!
If you are debating global warming you would do as much research on global warming as you could (reading books, searching the internet for scholarly journals, etc.) then of course form an opinion about it. When debating other people on the subject you will use examples to back up your argument from the research you have done. (It is also good to research what you think the other side will research. Find out what the opposition's main arguments will be and then work out how you are going to disprove them ahead of time so you aren't struck dumb in the middle of the debate by a statement that you don't know how to cannot combat in the heat of the moment.)
This is a really broad and general strategy but it does apply to all of the activities that you mentioned you need will need to talk about. Good luck!
Tyler