Some of the major steps would be:
Instruction set design where you decide what operations the computer will execute, how addressing of memory will work, security features, input/output, and how the instructions will be encoded and represented in memory.
Chip architecture where you decide on how the memory and processor are interconnected, how registers are laid our, how the registers work with arithmetic logic units for integer and floating point operations, how instructions are decoded, etc.
Circuit design which is usually at the building block level, rather than individual transistor and component level.
Floor planning, which lays out the circuitry in 2 dimensions and determines the routing of the wiring.
Simulations which “test” what you’ve done to better your chances that the chip will work.
Mask generation that creates the masks that will be used for the multiple steps of photolithography.
Purifying silicon and creating a pure crystal 12 inches in diameter and then sawing it into thin wafers that are then polished and etched to create a very flat crystal with few defects.
Wafer fabing, which involves many steps of vapor deposition , ion implanting, ultraviolet light exposure, washing and etching, etc.
Testing of the wafer to see if it is worth proceeding.
Dicing of the wafer with saws to make individual chips.
Bonding of the wafer into a ceramic package so that it can be connected to a circuit board by the customer.
Final testing of the finished processor.
I’ve probably left a lot out.
It seem you have the gist of it.