Hello! Congratulations on being hired on the spot during your interview at McDonald's! Based on your message, it seems like you are part of Batch 3. Typically, companies like McDonald's organize new hires into batches for training purposes. If Batch 3 is indicated on your group chat, it is likely that you are indeed hired and scheduled to start with that batch.
However, to be absolutely certain about your employment status, it would be best to reach out to your contact at McDonald's or the person who informed you that you were hired on the spot. They should be able to provide you with more information about your start date, training schedule, and other necessary details.
It's normal to have questions, especially if this is your first time applying for a job. Don't hesitate to seek clarification from McDonald's to ensure that you have all the information you need as you begin your new job. Best of luck with your new role at McDonald's!