Fetch - get instruction somehow. The method isn't important, that's why we call it Fetch.
Decode - What kind of instruction is this?
Execute - Do whatever the instruction requires. It may not be one thing.
I think I know what your doing and it may be because of your style of learning, You can probably memorize easily, but have trouble with concepts.
Memory can be a combination of visual, verbal and kinesthetic. The latter item is like learning by repetition or learning how to ride a bike.
Verbal is by reading or speech. How well can you take directions from a stranger?
Visual is just that. Vision. My doc could visualize an entire page of a textbook in his mind. it's hard in a forum to do a visual presentation.
Unfortunately, what you have to learn here is concepts, not 1+1=2. Concepts might be better presented visually.
Every computer, controller implements the Fetch, decode and Execute in various ways.
One concept that is important in this study is the CISC and RISC architecture. CISC means Complicated Instruction Set Computing and RISC means Reduced Instruction Set Computing. In the latter, each instruction generally required one clock cycle to execute and the instructions are simple.
To give you an idea of a really CISC computer, lets look at the VAX architecture. You can find a character with a machine instruction. See:
https://www.cs.auckland.ac.nz/references/macvax/op-codes/Instructions/locc.html
So, your definition falls out the window. With Fetch, Decode and Execute abstractly defined, it still is valid.