The first step in a CPU instruction cycle is

The first step in a CPU instruction cycle is Fetch.
During the Fetch step, the CPU retrieves the next instruction from the memory. This instruction is stored in the instruction register (IR) so that it can be processed further.
The Fetch step involves the following sub-steps: 1. The Program Counter (PC) keeps track of the memory address of the next instruction to be fetched. Initially, it points to the starting memory address where the program begins. 2. The PC value is transferred to the memory address register (MAR), which holds the memory address we want to access. 3. The control unit sends a request to the memory unit to access the memory location specified by the MAR. 4. The memory unit retrieves the instruction from the specified memory address and sends it back to the CPU. This instruction is stored in the Memory Data Register (MDR). 5. The content of the MDR is then transferred to the Instruction Register (IR), where it is held until further processing.
In simple terms, the Fetch step is like going to the supermarket and getting the shopping list (instruction) of what items you need to purchase. The CPU fetches the next instruction from the memory so that it knows what operation it needs to perform next.