Sounds exhaustingly normal to me!

Cooking is tough. I find if I let them 'help', they're often happy for a while. So on the floor or in the high chair next to me I give a small pot, a wooden spoon, the carrot-peelings and veg off-cuts and encourage DS to mix and stir. DD is older and has been participating in the actual cooking since a bit over 2 - chaotic but great fun!

I also sometimes resort to cooking with DS in the ergo on my back if he's being clingy.

As for screeching and screaming... yep. Normal. We get a whole lot of that too. Particularly (it seems!) when really early in the morning or late in the afternoon and I'm feeling a bit sensitive to loud noise, they both seem to really crank up the volume!