Yes, it is possible to change the group selection after registering for the CA Foundation Exam. Here's how:

1. Understand the rules: Before proceeding with any changes, it is important to familiarize yourself with the rules and regulations set by the Institute of Chartered Accountants of India (ICAI) regarding group selection changes. Make sure you are aware of the deadlines, fees, and any other requirements for changing your group selection.

2. Contact the ICAI: Reach out to the ICAI through their official website or helpline to inquire about the process of changing your group selection. They will provide you with the necessary information and guide you through the steps involved.

3. Check eligibility: Ensure that you meet the eligibility criteria for changing your group selection. The ICAI may have certain restrictions or conditions in place, such as a specific time period within which changes are allowed.

4. Submit a request: Prepare a formal request to change your group selection. This can be a written letter or an online application, depending on the process specified by the ICAI. Clearly state your reasons for wanting to change your group selection and provide any supporting documents, if required.

5. Pay the fees: There may be a fee associated with changing your group selection. Make sure to inquire about the amount and the mode of payment accepted by the ICAI. Pay the fees within the specified timeframe to avoid any delays or complications.

6. Follow up: After submitting your request and paying the fees, follow up with the ICAI to ensure that your application is being processed. Keep track of any updates or additional requirements they may have.

7. Confirmation: Once your group selection change request is approved by the ICAI, you will receive a confirmation. This confirmation will reflect the updated group selection for your CA Foundation Exam.

It is important to note that changing your group selection may have implications on your study plan and preparation. It is advisable to consider this decision carefully and consult with mentors or experienced professionals before making any changes.