Learn Hardcore Spanish (Latin America): Durante su discurso, el orador compartió historias sobre perseverancia. - During his speech, the speaker shared stories about perseverance.

durante means during. You use it before a noun to indicate a specific time period. You cannot follow durante directly with a verb; if you need a verb, use mientras instead.
Examples:

Durante el concierto, llovió mucho.
Mientras cantaba, la gente aplaudía.

Why is there su in durante su discurso? Whose speech is it?

su is a possessive adjective meaning his, her, their or your (formal). In this sentence it refers back to el orador—so it’s his or her speech. Spanish doesn’t distinguish between third-person possessives (his/her/their) with different words, so context tells you whose it is. If you needed to avoid ambiguity, you could say el discurso del orador.

Why do we say el orador instead of just orador?

Spanish generally requires an article before a singular, countable noun. El orador means the speaker. Omitting el sounds unnatural unless you have another determiner (e.g., nuestro orador = our speaker). If the speaker were female, you’d say la oradora.

What tense is compartió, and why is it used here?

compartió is the preterite (simple past) form of compartir in third person singular. It conveys a completed action in the past (“he/she shared”). Here it emphasizes that the act of sharing stories happened and finished during the speech. If you wanted to stress an ongoing or habitual action, you’d use the imperfect: compartía.

Why is it historias (plural)? Could it be historia (singular)?

It’s plural because the speaker shared multiple stories of perseverance. If there were just one, you’d say compartió una historia sobre perseverancia. Pluralizing shows that there were several anecdotes.

Why sobre perseverancia instead of de perseverancia? Are both correct?

Both prepositions work, but they have a slight nuance:

sobre = about/on (more explicit topical marker)
de = of or about (broader)
In practice historias sobre perseverancia sounds most natural when you want to highlight the topic. Historias de perseverancia isn’t wrong, but is a bit more general.

Do I need la before perseverancia, like sobre la perseverancia?

With abstract nouns like perseverancia, the article is optional.

historias sobre perseverancia (general, common)
historias sobre la perseverancia (slightly more formal or specific)

Can I move durante su discurso to the end of the sentence?

Yes. Spanish word order is flexible. You can say:
El orador compartió historias sobre perseverancia durante su discurso.
Putting the time phrase at the beginning or end doesn’t change the meaning.

What’s the nuance between compartió historias and contó historias?

Both mean “he/she told stories,” but:

contó historias (from contar) is a neutral way to say “narrated” or “told.”
compartió historias (from compartir) emphasizes the act of “sharing” something personal or meaningful with the audience.

How do I pronounce historias and perseverancia?

historias: ee-STO-ree-as (the h is silent; stress on the second syllable).
perseverancia: per-se-ve-RAN-sia in Latin America (the c before i sounds like s; stress on ran).
Remember: if a word ends in a vowel and has no written accent, the stress falls on the penultimate (second-to-last) syllable.