How to pull the layout of the checkout page?

Question

WooCommerce

In short, there is a design, html layout, you need to tighten it.
The only problem is that all these hooks and actions display fields and tables that are scattered across templates, which is extremely inconvenient. But the worst thing is that this page still needs to be in 3 steps, that is, I need to divide the checkout fields into 3 parts.
Some fields are custom (for example, radio buttons, the ones that are depicted as icons, I mean css manipulation with labels, icons)

Does anyone have any ideas how to do this?
I accept even the most daring ideas, because I did not find absolutely anything on this subject on the Internet and I assume that these secrets, you colleagues, keep under your pillow. If not greedy, then share.

Answer 1

If anything, I know where the default templates are and the advice is to copy them to your topic and edit, this is such advice.

Answer 2

If anything, I know where the default templates are and the advice is to copy them to your topic and edit, this is such advice.
But here there is no other way, often the design is far from what the standard functionality offers, and here the only way out is to edit for your theme, and through functions, cycles, hooks, bring it to the look you need.