Seeing how Instructions get Translated (Computer Architecture)
This question is too broad to be answered here -- it would take a book -- but luckily, that book has already been written : "The Elements of Computing Systems: Building a Modern Computer from First Principles" by Noam Nisan and Shimon Schocken.

The hardware is first discussed, starting from a low level (combinational and sequential logic gates, ALUs and memory), and then shows how these relate to the machine instructions.  The book also covers a compiler for a high-level language, and an operating system.

An Appendix describes the hardware in HDL (Hardware Description Language).