Prebiotic foods are rich in insoluble fibre which break down in your gut to short chain fatty acids, which help with providing energy to the cells lining the colon, and also to feed certain beneficial microorganisms in your gut biome. Your digestive tract is meant to have trillions of beneficial microorganisms such as bifidobacteria. They help to digest food which in turn helps your hormones and your immune system. If the microorganisms are well balanced and thriving this can help you to be more resilient and healthy.
To keep them "fed" well then it is important to reduce consumption of processed foods, in particular ultra processed foods. Instead swap in whole foods such as vegetables and fruit.
Typical well known prebiotic foods include:
Bananas (green rather than over ripe)
Jerusalem artichoke (aka sunchokes)
Milk (from grass fed/organic/biodynamic sources)
Oats (whole grain)
Whole grains (not processed but the literal whole grain such as brown rice, barley, millet)
As a health coach I can help you to make healthier choices. Please use my contact page to have an initial discussion.