Intellicus Technologies interview question

In both technical rounds: Intro, Projects and Internships(explain only), OOPS(implement Polymorphism and Inheritance), JOIN query(LEFT JOIN), Linux commands: top, scd, permission(read, write and execute),pwd,etc. It took 1 hr to complete 1st Technical interview and 1hr 30 min to complete 2nd Technical interview. I was not able to clear the 2nd Technical interview because of nervousness and lack of communication skills, so be confident and then give the interview.