Hello @churongcon ,
Thank you for the request and sorry for the delay in reply.
Kindly, please, be informed that a single course actually is not a page or a post. It is a unique custom post type with its own style and some elements could be not available for edition by default settings.
As an option, we would like to offer you to change it to the default styles that are available in the MS LMS > LMS Settings > Course > choose Course Page Style section https://docs.stylemixthemes.com/masterstudy-lms/lms-settings/course
Additionally, could you please clarify what exactly changes you would like to make? This will help us understand how we can enhance our product and service to meet your needs and ensure your satisfaction.
Best regards,