No. It could be phrased as "It is very useful in one's day to day life."
Student or Learner
Would you, please, tell me if the following sentences is correct?
It is very useful on the day to day life.
I'd suggest "day-to-day" with the hyphens.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.