What is Energy and Work?

I'm sure most of you have come across this question many times and may be reluctant to answer because you have answered this before, but I still feel the need to ask this.

Recently, I came across the question in my own mind while studying, and as soon as I thought about it, I quickly realized I had no clue what these things were. Over these past few days, I have read countless threads giving answers, but every answer feels like it's always missing something. The question has left me unable to think about anything else, and I feel that if I don't come to terms with what they are, I won't be able to learn anything else.

Most answers try to define energy as the capacity to do work. When asked what work is, they either define it as the force applied to an object to induce a displacement or as the transfer of energy. However, the transfer of energy definition feels very circular.

I struggle to see what it is in objects or nature that made physicists make these definitions. I guess the essence of my question lies in what energy and work actually represent in the real world. Feynmans description of energy helped a bit, but when I look at physics problems involving this "kinetic energy", it feels as if the concept itself must have been based on some natural observation/phenomena in moving objects. The question is also what is it based on?