A business is never small or big. Its just our hard work and perseverance. There are various startups you can start in large areas like Delhi or Bangalore.
You can start a travel agency, as travel agency has witnessed a boom in the past decade. Keeping to people’s changing habits and their desire for the ultimate ‘wanderlust’, the time is ripe for aspiring entrepreneurs to put their money where the map is.
You can start a small mobile recharge shop, Because India's most mobile-users prefer visiting a recharge shop to fill their balance. So those looking to practice this business can start by renting a space in a small local shop.
You can start a small breakfast joint kind of thing if you are low on budget, because food as a commodity will always do well in a competitive market.
There are several other ideas which you can think of, like tuition center at your home, fruit juice corner, tailor shop, bakery shop, and many more. As there is no limit of ideas.