Adding photos to post above

Ir'a LOVELY quarter sawn oak Mission style cabinet. I would remove most of the finish with a solvent....I like 3 parts denatured alcohol ( also called shellac thinner) and 1 part acetone ( also called lacquer thinner). Swab it on and wipe off with rags or paper towel....outside....that mix is flammable! Then either leave it as is....or put on a coat of poly urethane or varnish...or shellac.

Thanks Linda, I'll try that. I'm thinking of just doing the one drawer front and seeing how it fits in.

Your local glass and mirror shop can cut new pieces of glass to fit. They can also make glass shelves if those have been lost, but don’t buy glass thinner than quarter inch for the shelves. Single strength glass is for the cabinet doors and sides only. It would not hold any weight if you try to use single strength for shelves. Pay the extra money to have a polished edge put on the shelves. You could also talk to antique shops about a good refinisher in your area. It would not be cheap, but this piece has its own charm in addition to the sentimental value.

Thanks for the advise remodelling. I only want to clean this piece if it comes to refinishing I will have it done professionall. The shelves are wood and I have them so the plan is to clean and use them. Thanks for your safety advise I will not leave them in the house or garage.

Any rags inside or out should be placed in a metal container as you discard them until you can take them outside. Some can generate a large amount of heat. The fire department suggestion here after a garage fire was to place the metal container at least 3 feet away from anything flammable including trees with low hanging branches and shrubs. Many hardware stores, in this area, sell the old fashioned metal trash cans for this purpose.

The cracking may be a old shellac finish. It can be re-amalgamated if it is shellac.

https://home.howstuffworks.com/home-improvement/home-diy/projects/how-to-restore-wooden-furniture-finish1.htm

As said before rags should be stored in a air tight container, even add some water. It can spontaneously combust.

Thanks Izzy great article. I might give it a try on another area that has a lot of crackling on the side.

I was happy to find that article too. I refinished a old cabinet that was my grandfather's that had a shellac finish and couldn't remember what I used.

Check out this thread that talks of a kind of similar situation as yours.

https://www.houzz.com/discussions/5795527/should-old-wardrobe-be-refinished-or-just-rejuvenated

I haven't read the whole article yet but yes it sounds simila. I have done a bit of refinishing and took a night school course that was very basic for beginners but I think I could very easily get in over my head. Thanks so much for your help. I plan to do the reading and giving it a try.