Hi @gem717,
A warm welcome to the Bunnings Workshop community and thank you for your question.
You'll have to start by removing the varnish from the surface of the cabinet. You can either sand it all off or use a combination of Tricleanium Paint Stripper and sanding to remove the varnish. If you plan to use a chemical stripper, make sure you do it in a well-ventilated area and wear gloves, protective clothing and a mask.
Once the varnish has been removed, you can paint the cabinet in a colour of your choosing. The range from Porter's Paints would look fantastic.
Another option is to limewash your cabinets. You can check out @prettyliving's guide on How to lime wash timber furniture for some easy-to-follow, step-by-step information on the process.
Let me know what you think and if you have further questions, please don't hesitate to ask.
Jacob
