Wipe it over with Wet Wipes (You can now buy "Green" ones) to get of the
residue, do that a long as stuff is coming off. Let dry and then wipe over the keys with a cloth soaked in milk, and squeezed out. Use a good furniture polish to do the rest. If you have brass foot pedals use a metal polish on them.
Murphy’s Wood Soap might do a better job on the smoky residue.
Spray Nine is good for removing stains due to smoke, etc. Available at your local hardware store.
Vinegar on what you can get to but......you probably need it professionally cleaned because you cannot clean the insides very well unless you know what you are doing,the nicotene gets in the felted wool on the keys and it needs replaced, completely wrecks the true sound;nicotene settles on/in everything. Lived with 2-3 pack a day piano player-guitar player 20yrs. https://www.piano-tuners.org/piano-forums/viewtopic.php?t=3546 easy fix for the outside wood case is 50-50 linseed oil and white spirit(mineral spirit used by artists), cleans and oils at the same time; get white spirit https://www.amazon.com/Winsor-Newton-Artists-White-Spirits/dp/B00681M9JA/ref=asc_df_B00681M9JA/?tag=hyprod-20&linkCode=df0&hvadid=167130062341&hvpos=1o3&hvnetw=g&hvrand=8299194808035314569&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030040&hvtargid=pla-310347763577&psc=1 or craft stores(more $) good luck