I am asked about loads for muzzle loading shotguns quite often – in fact about as often as I ask other people about loads for muzzle loading rifles!
The answer is that within reasonable limits there is variation in what people use, and I’m sure whatever I say those limits are, someone will pop up and contradict me! This is strictly my own version of what to use and how to load, modified slightly for beginners – you may cut corners when you have a bit more experience;-