Natural Resources Wales provides advice on their website on how properties may protect themselves from flooding, including links to other relevant external resources: https://naturalresources.wales/flooding/preparing-for-a-flood/?lang=en
There is also an explanation on different kinds of property level protection available on: https://www.floodtoolkit.com/ox-cam/
The Floodmobile virtual tour is a good visual resource, and the homeowners guide to flood resilience offers a clear overview of flood protection products available.