Generally, less than three is too few and more than five is too many. Most speakers plan three main points. List the ideas, considerations, and evidence that relate to each main point. At this point, write freely, suspend judgment, and consider possibilities. Collect more information than you expect to need because you will sort it out in the next step.
Most people chick their content for accuracy.
Use reliable data, check resources, and make sure your evidence supports your conclusions. Many people are afraid of speaking. They expect that they will make mistakes that cause catastrophic ruin. We all learn and grow from our mistakes. You gain confidence by achieving competence.