100% agree gut health is the key to healthy immune system are you also have healthier skin and more regulated moods and hormones lots of tips that I can share on how to achieve gut health because it's definitely more than just one thing

A really good thing that you can do to encourage healthy God is to reduce processed sugars and processed foods and introduced a lot of whole food into your diet so that the flora balance in your gut is more balanced

Secondly I would introduce probiotics and fermented foods of course all of the suggestions I would recommend you consult with a health coach or a functional medicine doctor a nutritionist who can specifically give you recommendations that are best for you