How does the microprocessor work?

Suppose we give a 8-bit instruction ADD B to the microprocessor

then this instruction is not at all understood by microprocessor as it only accepts binary inputs

so first of all it stores the instruction in the INSTRUCTION REGISTOR

then it decodes this instruction ADD B to its suitable binary code 80H in the INSTRUCTION DECODER.. after converting to 80H then the microprocessor understands that ..

yes i have to add the content of the resistor B with that of A(accumulator) and store the result in the accumulator A

this is a small example how microprocessor operates facing the instructions