Clean well, scuff up with a green kitchen scrubby, prime with Kilz primer, and paint. Seal with three coats of a water based polyurethane.
Prime it well, and paint 2 coats. Sounds like a fun project!
I did a similar project and I sanded it well,using several grits of sand paper, then I used a tack cloth to make sure I got up every bit of grit. I used Kilz to prime then lightly sanded and used the tack cloth again. Finally I painted it with latex paint - 3 thin coats for durability. Wishing you the best.
I would scuff sand it first with 220 grit sandpaper and then prime it really well with an oil based primer or shellac based primer like BIN. Then you can proceed as normal. Here's a tutorial on how to paint furniture https://www.arayofsunlight.com/how-to-paint-furniture/