No idea what to do!!

I am just about to complete my first project. I am making a bookcase and cabinet from MDF and topping the cabinet with 32 x 190 kiln dried tassie oak, the oak has been buscuit jointed togeather along its length. I need to put a finish on it but I have no idea where to start. I would like to match the top to an oak desk that we have in the room, the new oak looks quite pink. Can anyone give some advice...... What grit sandpaper should I use to get rid of the high spots.

Thanks for any help!!

why use the mdf the 32mm tas oak is more than strong enough without it.

The MDF is just for the carcasses. I am using the tassie oak as a 'bench top' to break up a wall of MDF