Once you find the sites that interest you, you can start asking and answering questions. This is the core activity of Stack Exchange, and it allows you to learn from others, share your knowledge, and get feedback. To ask a question, choose a site that matches your question topic and level of expertise. Use the search function to see if your question has already been asked and answered. If not, click on the Ask Question button and write a clear, concise, and specific title and body for your question. You can also add tags to categorize your question and make it easier to find. Review your question and submit it. To answer a question, browse the questions on the site or use the tags or search function to find questions that you can answer. Click on the question title and read the question and the existing answers carefully. If you have a new or better answer, click on the Answer button and write a clear, detailed, and relevant answer. You can also use code blocks, images, links, and formatting tools to enhance your answer. Finally, review your answer and submit it.