How to Simulate Key Press for Scripts?

Hi, I'm fairly new to MCreator and I'm not sure how I can create a script with this mod.

Ideally, I'd like it so that it can control the player's movements and keystrokes without the player having to input (say maybe it can walk around a farm for example).

How can I use MCreator to make it so that pressing a key will start running the script so that it will say hold "d" for 10 seconds, then "a" for 10 seconds.

Thanks