Indian English is a legitimate variety with its own history. But if your goal is to be understood easily by speakers from other countries, a handful of habits are worth adjusting.
"Do the needful"
Widely used in Indian offices, widely puzzling elsewhere. Replace with what you actually want: "Please approve this" or "Could you update the record?"
"Revert back"
Outside India, revert means return to a previous state, not reply. Say "get back to me" or "reply when you can".
"I am having a car"
Have for possession does not take the continuous form. "I have a car." The continuous works only when have means an activity: "I'm having lunch."
"Discuss about"
Discuss already contains the "about". Say "Let's discuss the budget", not "discuss about the budget". The same applies to order ("order for") and marry ("marry with").
"Only" in the wrong place
"I came yesterday only" is natural in Indian English but reads oddly elsewhere. "I only came yesterday" or "I came just yesterday" is clearer.
"Kindly" everywhere
Grammatically fine, but it sounds old-fashioned and slightly stiff to many readers. "Please" does the same job with less formality.
Prepone
A genuinely useful word that simply does not exist outside South Asia. Say "move it earlier" or "bring it forward".
Question tags
"You are coming, isn't it?" should match the verb: "You are coming, aren't you?" The tag mirrors the main verb and flips the polarity.
None of these are failures. They are regional habits — the same way British and American English differ from each other. Adjust them only where your audience makes it worth doing.
