I mostly let my son entertain himself lol. Pottering around outside in the garden is always the best.
But for fun activities - baking - they can help mix, pour things into the bowl, if it's something that is rolled and cut then give them a little rolling pin and their own little bit of dough to roll out. Doing dishes - fill up the sink with water and bubbles and let them go for it (towels on floor required

) Painting - sounds like he'll probably eat a bit though lol. Blowing/chasing bubbles. Make a house under chairs or something with a sheet hanging over (good for running through and playing peekaboo).