They love all fresh food
. And most human food. And will try snd take it out of your mouth if you’re eating something. A lot isn’t safe though- eg anything in sauce or with salt or spices - veg, oats etc are fine.
Another way of making platforms is IKEA Knuff magazine racks. If you put IKEA Knuff hamster shelf into Google and click on images, you’ll see what I mean.