Please consider doing something unique. That is, doing something that does not exist in your area.
My best advise would be to continue to be in business, and build a good fortune by going into businesses where there is very less competition, or none at all.
Though I do not know where you live, near your place, check if you can rent out a small place. Once done, engage some very good cook who knows South Indian dishes. Since such people are available in Chennai, or even down South in places like Madurai, and you need to identify one or two cooks. If it is a poor family, and both husband and wife can migrate to your place, that would be a very fine option.
You also need to train at least one local fellow, who can also act as an substitute. Sometimes, these people are also available on a part time basis. Please do remember, iddli, vada and dosa are now national dishes, and are eaten more by those in North India, than even South Indians, in cities like New Delhi.
For example, a superb restaurant like Saravana Bhavan, from Chennai, which is premium priced for its very tasty vegetarian dishes, is so famous in New Delhi, and one has to do book in advance for a seat.
You do not need to go that extent, but the logic is to do a busy with minimum investment, and maximum return, as it is a cash and carry business. No customer can walk away without giving cash.
In fact, if you want to get some ideas, come to Chennai, and visit some of the small restaurants that have sprung up in every single locality. When you observe their style of working, they always work in a small way, and make huge profits on their very limited extent. The big variables are the taste of the chutni and the sambar, which is a vital side dish. If you have some good Tamilian or Kannadiga friends, you can ask the ladies, the recipe for good sambar.
Alternatively, try something like the DTP services which have a huge demand. Take up xerox initially, but graduate to offering services like changes in PAN card, Aadhar card, getting the passport, and so on. This business does not require huge investment, but only skill. Am sure you will be able to do well.
Also think of trading in unbranded textiles. You can buy these cheap from Surat, and sell them in your place. Do any of these and you will succeed in business. So, go for businesses without huge investment, but where you can get good cash flow, like the small restaurant business.