I believe this is the high time to show what you can do by using your skills and ability. Though you are a fresher, as you said above, you were still selected and provided a chance to work with your employer. Your boss is expecting you to perform, so I would say you must search for options that can help you in performing or using your skills instead of taking much stress with these things.
Also, the people who have selected you are very well aware of your qualifications and skills, and they know you don't have experience (fresher), but they still trust you and are expecting you to perform. This means you have a good opportunity to learn and apply your knowledge.
Solution:
- The very first thing that you have to do is to make a note of whatever your boss is asking you to do.
- Discuss the same with your colleagues and friends who are in the same work profile (inside and outside of the office).
- Read the documents, threads, and available material related to the assigned task in this place.
Lastly, I request you to share what is actually bothering you here, as you haven't shared such details except your boss's high expectations. Until you share your problems, the community won't be able to help you with your problem properly.