How to stop feeling inadequate and ill prepared for anything I attempt to do in life?

I'm glad you like my answer to your Anthropology question. Here are a few more ideas.

You might want to read a good book on how to do your freshman year. I'll tell you a good way for selecting books at the library - something useful for research. You can also use this with several books from Amazon if they're cheap. If you see a number of books on the same subject, how do you decide which one is best? Let's say you're doing a paper on the study of electromagnetism and there are lots of books. Do a benchmark test. See how each book treats a particular topic, such as Hertz and other people who discovered radio. Look for the best explanation, right amount of detail, good structure, clear writing. That tells you what the best book is.

Amazon sells a few books about the first year of college/university. Your library may have them.

The Internet has a variety of "how to survive your first year of uni," "first year of college" websites. I suggest looking through them. See if there are ideas that you spot on more than one site.

Stress management is something we all need. We live is a stress-filled culture. My previous answer has stress advice. Another good source - Dr Steve Ilardi, psychologist and self-help author, expert on lifestyle.

A subject you might find interesting is a theory worked out by a psychologist named Albert Bandura. He is known as the originator of social learning theory (renamed the social cognitive theory) and the theoretical construct of self-efficacy. He came up with good advice for people who lack self-confidence.

are you ready? experience enough to do it? being at the right place at the right time is luck but when you feel you are not ready or experience enough to make use of that luck, then it is a wasted luck