Learn Hardcore Russian: Сегодня утром я купила свежую булку и маленький пончик в новой булочной. - This morning I bought a fresh bun and a small doughnut at the new bakery.

inanimate: accusative = <a class="border-b border-dotted border-blue-400 dark:border-blue-500 cursor-pointer text-inherit no-underline" href="/grammar/russian/cases/nominative/forms-and-subject">nominative
animate: accusative = <a class="border-b border-dotted border-blue-400 dark:border-blue-500 cursor-pointer text-inherit no-underline" href="/grammar/russian/cases/genitive/forms">genitive

Breakdown of Сегодня утром я купила свежую булку и маленький пончик в новой булочной.

Why is the verb купила and not купил?

Because купила shows that the speaker is female.

In the past tense, Russian verbs agree with the subject in gender and number:

So this sentence tells us that the person speaking is female.

Why are булку and пончик in different forms after купила?