How do I regenerate a microbiome?

Eat a wide variety of foods, especially fermented foods (like real yogurt) and foods high in fiber. Supplement with probiotics and inulin.

For lots more, Google this query: increase microbiome diversity inulin yogurt probiotics

If you want to see how diverse your microbiome is or becomes, buy a mail-in test from Viome (or if/when it relaunches, uBiome).