I have applied for clat but unfortunately I couldn't get an adequate rank. So should I drop this year or dropping would effect in future?

Totally worth the effort.

But only if you are able to secure a seat in a Tier 1 NLU, which are:

NLSIU, Bangalore

NALSAR, Hyderabad

WBNUJS, Kolkata

NLU, Jodhpur

NLU, Delhi

CLAT is an exam which you can very well prepare alongside a full time Bachelor Degree course.

My suggestion would be to take admission in a graduation degree, enroll for coaching in a credible institute & appear for the exam again.

A lot of my batchmates from law school have done so and all of them are doing well in life.

Make a choice!

Good Luck!