Q: How can I remove everything from my current iTunes and start a fresh? Kindly help

Hey Rajat De,

If I understand correctly, you want to use iTunes, and it to be a clean library to start from scratch. I would recommend you read this article, it may be able to help troubleshoot the issue. 

You can delete all of your content or you can create a new library that is empty and add you content to that library. 

Open a different iTunes Library file or create a new one - Apple Support

Thank you for using Apple Support Communities. 
Have a good one.