The Central Processing Unit aka ‘CPU’ aka ‘processor’
Its not really that hard to understand how the cpu works.

The first thing to understand is - whenever we start a program, their instructions are stored in memory to be executed by the CPU.

It fetched the instructions, understand it and decode the instructions as well as to determine what it has to do. The CPU will do some sort of computation, stored it back to memory, the disk and the display.

The next step is for the processor to understand or decode the instruction and determine what it has to do. Usually what happens is that the CPU will do some form of computation, then stores it back to memory, the disk, or the display.

How many instructions can the CPU execution per second? this is determined by certain factors, including:

How large is the instruction contained in memory

How long it takes for the instruction to reach the CPU.

How long the processor takes to compute and crunch the instructions.

How long it takes to output the result of the processing.

Essentially, the number of instructions a CPU can execute per second is an indication of its speed and performance.