If South Africa currency rate is better than Brazil and people come to visit here but they are from brazil wil it be beneficial to South Africa and why

In the long run, no.

Whenever there is an increase in immigration, we will experience a short period time of growth due to an increase in productivity level.

But, Immigrants tend to send the fruit of their labor back to their families in original country, which means the capital is not distributed back to South Africa but rather to Brazil