Can I prepare for IAS just by studying 3 hour everyday?

I am telling you some ways that you can follow to reach there:
  1. Download joshjagran app at your mobile phone, for all the current affairs topic wise and try to read them during your travel time if possible, it hardly takes your half an hour.
  2. Read NCERT twice or thrice as it would be helpful to make you conceptually strong at your points.
  3. Two subjects at a time, divide your time equally.
  4. Notes ,you can take notes of ias institutes as many are providing distance learning programmes for people like you.
  5. Read The Hindu daily anyhow, this newspaper is the heart of UPSC ,you can't ignore it.
  6. Write, if you are not able to make it daily then on weekends, whatever you read the whole week you just write it all ,no matter good or bad ,write it like a story and you can feel the difference thereafter by yourself.
  7. Analyse. Start analysing the things around you and start thinking about the other part of the coin,provide solution of each and every problem to your head, it will make you problem analyser and would be helpful during your mains.
  8. Be motivated.
  9. Never lose your hope.
  10. Be consistent and be regular with your studies time.
Last three points are the key factors,believe me, as the famous proverb says:
Success demands only 5% of knowledge and 95% of your confidence. 
But always remember that without this 5% of knowledge , you can't gain that 95% of confidence.
Hope it helps. All the very best.