this python script generates about 144M private keys with the X and Y keys, which takes a long time to generate, so I'd like to know if it would be possible to speed up the process by keeping the calculation method used in the script, even if it's just a matter of generating the private keys while keeping the calculation method?
144M private keys are a drop in the ocean of keys. What's the point of generating public keys from private keys (it takes a long time). You need to add and multiply and divide public keys (XY coordinates). The process can of course be speeded up if you use C++. Not a single Python script has yet found complex solutions to a puzzle.