Indians in Jo'burg (Johannesburg)

Hello - I am an Indian moving to Jo'burg next month with family from NY. I would like to get some insights/tips about the Indian Grocery, Indian festival celebrations, language classes, etc. around Sandton. I would of course love to connect with non-Indians as well who have recently moved to Jo'burg, esp. from the US as the do's and don'ts would be quite fresh in their memory. Any piece of information will be quite helpful. Thank you in advance!
Best, A