How can I have two mice and keyboards, one pair controlled by a program?

I want to create a program that automatically does some tasks on the computer. I want these tasks to be done at the same time as the user is doing their own tasks. In order to do this, I would need to simulate a mouse and keyboard.

I want the two pairs of mice and keyboards to work separately, for example if program selected a textbox at the same time that a user selected a textbox and both the user and the program type something, I want what the user typed to go into the textbox that the user selected and what the program typed to go into the textbox that the program selected.

How can I do this? Thank you very much :)

I've tried libraries like pyautogui and others but they control the user's mouse and keyboard. I want the program to control its own mouse and keyboard.