MerceHygeaSurface Saver Vance 20 X 16 inch Clear Tempered Glass Cutting Board, 20 X 16-Inch

Q: Is this smooth on one side and pebbled on the other?

Slight pebble on top & smooth on the bottom

Q: can this be used to set a hot appliance on it, like a slow cooker or an air fryer?

The Surface Saver is used to cut, chop, and set hot plates/pots/pans and is not recommended for the use you reference.

Q: If I make homemade fudge and pour hot chocolate/fudge on this would it be able to withstand the heat?

I believe it would. I put hot pans on mine right from my stove. I would use some wax paper though. The surface has a texture. I truly love these boards. I actually have 3. I put them everywhere to save my counters.

Q: "How to details" needed for installing ss frame/counter saver and damaged existing laminate countertop.

There is a built-in frame available (sold separately) for installing this directly into the counter top. Search for: 16 X 20 Stainless Steel Frame for Built-in Tempered Glass Surface Saver Cutting Board