Find some veneer to match the cabine cut a piece to match the area that is missing and glue it in with contact cement (no clamping is needed with contact cement just follow instructions on the glue) You can get a t Lowes or Home Depot. You can also use a good wood glue like Weldwood or elmers but you will have to apply pressure until dry.The loose veneer can be reglued with wood glue by using a hypo needle to get glue under the veneer and clamp down with wax paper between the the clamp and the veneer. You can use a flat piece of wood between the clamp andwax paper to help keep the veneer flat while the glue sets overnight. You will have to lay the cabinet on its side with area you are working on up so it will be easy to clamp or place a heavy object on it to keep the veneer flat. Once repairs or done you can apply a little stain to the area to match the rest then apply a thin coat of shellac over the repair. I f you have any questions feel free to ask them here.
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