Will Falconer, DVM Moderator
Lots of food choices, Rumy. Here's a page to start you out: https://vitalanimal.com/feed-for-vitality/
And the "good immunity" she's likely got at her age is from her mom. It's called "passive immunity" and only lasts till 12-16 weeks or so, and then it disappears.
So glad you're starting this one out naturally!