How to buy tokens on ICP?

Hello there, I'm interested in learning more about purchasing tokens on the Internet Computer Protocol (ICP). Can you please walk me through the step-by-step process of buying tokens on ICP? What are the necessary prerequisites I need to have in place before I can start buying tokens? Are there any specific exchanges or platforms that I should use for this purpose? Additionally, are there any security measures I should be aware of to ensure the safety of my investments? Your guidance would be greatly appreciated.