1. The first step is to create a questionnaire and choose an online questionnaire platform, such as questionnaire and Tencent questionnaire. On these platforms, create a new questionnaire and select the "Exam" type. During the process of creating the questionnaire, enter the exam name and description, and then click Create Exam.

2. Step 2: Add a theme. After creating the questionnaire, click Add Topic and select the topic type and theme template as needed. Create a multiple-choice question, enter the topic, and fill in the topic options. The box in front of the option is used to check the correct answer, and you can also add pictures to the option. Click "OK" after setting the topic score, and the confirmed topic can be modified again. After all the questions are entered, click Preview to see the effect of the questions.

3. Step 3: Generate a QR code. After entering the question, click "Publish Exam" and select "QR code" from the published options. In this way, you can get a QR code, which can be used to scan the code to answer questions.