Hi Tanya, here's a step by step tutorial, hope it helps! https://www.thespruce.com/steps-to-clean-kitchen-cabinets-1900630
Here are some articles on Hometalk on how to clean them: https://www.hometalk.com/search/posts?filter=how%20to%20clean%20kitchen%20cabinets
I like to use very warm water and Murphy's Oil Soap to clean mine. Here are some more ideas.
OrangeGlo for normal maintenance.
Baking soda & hydrogen peroxide in a paste for build up. If that doesn't get it, then GP66 or Fuller degreaser. If you use a degreaser make sure it is wood/kitchen safe.
This is what I use for pretty much everything in my home, https://bushraslifestyle.com/diy-cleaning-caddy/
Hope it helps- Bushra