I got 5.5k rank in comedk so for better future i should join in b.tech or degree+civils coaching academies?

See it depends upon how interested you are in your field like there are people earning huge after doing btech and even there are many who are sitting in home because they don't want to put effort or lack in confidence. Think in your mind what should you do and believe me don't think for what will happen after 4-5 years it all depends upon how you are doing today,  if you put efforts today you ll be successful tomorrow and that's a guarantee.