My cats won’t play with regular cat toys they never have. But they have a great fascination with silly things like the rings from the tops of milk bottles or the caps from soda bottles. So I just save those and let them play with them.
Sometimes I will tie a string to the milk ring and pull it across the floor and they just love to chase it.
For “treats” I just saved the plastic container from one of those store bought treats with a lid and put some of their dry cat food I have now in it. I shake it, they come running. They don’t seem to notice that they are not yummy different “treats” because they come out of the “treat” can.