Sorry if my question here sound stupid because I got no experience with cabinetry

I'm wondering those cabinet with built in oven, does the wood come into contact directly with the oven or is there another layer of heat insulation material? Especially for the bottom part

If there's a heat insulation layer can anyone share me a link to purchase?

Usually oven will be mounted without touching the cabinet

Can share what is used to support the oven? Is it some sort of bracket?