Apply a chemical paint remover to the surface of your wood wall. Make sure it's safe to use on wood. Use liquid removers for one or two layers and semi-paste removers if there are multiple layers on the wood wall. Spread the remover evenly with a paintbrush.
Use a wood scraper to remove the paint once the paint remover has had a chance to work. Follow manufacturer's instructions for how long to allow the paint remover to stay on the wood.
Scrub the surface with an abrasive scouring pad once the majority of the paint has been removed.
Rinse the wood wall with clean water and let it dry completely.
Sand the wood using a power sander to remove any final remnants of paint and to prepare the surface for a coat of stain or new paint.