A standard computer is only capable of working with a binary system, which means it can only work with two states of information, that either being 1 or 0. In order to process the complexity of input information, the computer has to apply logic combining the set of two in order to produce the correct output.
This happens inside of a CPU thanks to tiny electronic components that form circuits. These circuits combine the binary input in simple logic gates that can generate specific binary output based on the nature of the input.
For example, the “not” circuit, reverts the input signal value, so if the input is 1, the output will be 0 and vice-versa. Another type of circuit, “and” only outputs 1 if both inputs are 1. These individual circuits perform simple logical calculations and are weak on their own, but combined together they can process more complex tasks.
The whole concept of computer’s computing power is to divide complex task into small primitive logical calculations that even a human could easily calculate. The advantage of computer is, that a single CPU has millions of these circuits and because electrons travel at almost the speed of light, one single CPU can calculate billions of these operations in a single second.