I'm no longer a sahp and came on to say - not a lot! And it varied day to day whether the kids let me get on at all.
I would meal prep for the day in the morning while DH had some time playing with the little ones.
I put baby in a sling to do a few chores. Didnt work too well tbh.
Once kids were toddling they "helped me" clean and cook and garden and grocery shop. They loved: supermarkets, vacuuming, cleaning windows, polishing and dusting, sweeping, making beds, hanging out washing on the line (handing me pegs, good for counting practice!).
Once they could sit up alone, I would clean the bathroom surreptitiously while they had a long bath. (Hint: if you have hot water in the morning sometimes a morning bath is lots of fun on a rainy day!)
At mealtimes frequently I would get an old folded-up duvet (kitchen floor is cold in my house) to use as a big playmate. The duvet, being warm and soft, encouraged ds not to spread his games all over the kitchen. Then DS had his own tub of uncooked Aldi fusilli to play with - labelled DO NOT EAT so I didnt cook it ever - I gave him saucepans and wooden spoons and plastic mixing bowls and he would endlessly pour it from one bowl to the next. He hated sitting in a high chair while I worked. At the end we would play "tidy up" and sweep it all into the bowl again. He slowly progressed onto a plastic child-care knife and now he can stir very competently, crack eggs, pour, and chop soft fruit and veg like peppers!
Now I'm back to work and the challenges are very different but... finally found a marvellous cleaner so that's one problem solved!