focus on the amount it costs to produce 1 BTC in terms of mining costs, what is that value and how do we calculate that?
Bitcoin is not a product that means that
bitcoin price is not decided by its production cost.
What you are asking only works for products, like a car for example. They have a production cost and that decides what the finial value of it is. But in case of bitcoin the only deciding factor is the utilities that bitcoin provides and the supply & demand (or adoption) of it.
Even more interesting is that for bitcoin the "production cost" (ie. the mining cost) is decided based on bitcoin's price not the other way around.