i have a backlogs in diploma can i join to btech its possible or impossible

Yes, it is possible, but it depends on the admission rules of the university or state.

If you have backlogs in your diploma , most colleges and universities will not allow you to take admission into B.Tech (Lateral Entry) until you have cleared all the required subjects and obtained your diploma certificate.

However, some institutions may grant provisional admission if you are expected to clear your backlogs within the prescribed time before the course begins or as per their admission policy.