Indian English habitDo one thing
Indian English: introduces a suggestion or plan.
Do one thing, call me after lunch.
Here's an idea / why don't you Works everywhere: a friendly way to suggest something.
Why don't you call me after lunch?
Remember: Clear to Indian listeners; international listeners may wait for 'one thing'. Say 'Here's what we can do…' so everyone follows.
Short lessonIndian English habitsIndian English is a real variety. Some phrases need a switch for international listeners.