Learn Hardcore Turkish: Lütfen yalnızca gerekli dosyaları gönder, diğerlerini sonra yollayabilirsin. - Please send only the necessary files; you can send the others later.

gönder is the neutral/standard verb you’ll see in apps, emails, and formal contexts.
yolla is more colloquial/informal, common in speech. In your sentence, using both is fine: the first clause is a direct request (gönder), the second gives permission with a colloquial feel (yollayabilirsin). You could also say gönderebilirsin instead of yollayabilirsin for a more neutral tone.

Why is it dosyaları and not dosyalar?

Because the object is definite/specific, so it takes the accusative.

dosyaları = dosya + lar + ı → the files (specific) as a direct object
dosyalar (no -ı) would be indefinite: “send (some) necessary files,” which changes the meaning.

How is diğerlerini formed, and what’s the -n- doing there?

It’s built from diğer (other) and behaves like a pronoun meaning “the others.”

diğerleri = “the others”
Add accusative to that: diğerlerini = “the others” (as a specific object) The -n- is a buffer letter inserted between a possessive-like ending and a case ending: diğerler+i (the others) + (accusative) + n + i → diğerlerini.

Could I say diğer dosyaları instead of diğerlerini?

Yes. diğer dosyaları explicitly repeats the noun “files.” diğerlerini avoids repetition and is perfectly natural when the noun is obvious from context. Both mean “the other files” here.

Can I replace yalnızca with sadece or yalnız?

sadece: very common and neutral; fully fine.
yalnızca: a bit more formal/literary; also clear and safe.
yalnız: can mean “only,” but also “alone” or even “however” at sentence start. It can be ambiguous, so yalnızca or sadece is usually better for learners.

Where should yalnızca go in the sentence?

Put yalnızca immediately before what it limits:

Yalnızca gerekli dosyaları gönder = Only the necessary files (not others). If you say yalnızca gönder, it would mean “only send (don’t do anything else),” which is a different focus.

Can I move sonra to other positions?

Yes. Common options:

Sonra diğerlerini yollayabilirsin.
Diğerlerini sonra yollayabilirsin. (your sentence)
Diğerlerini daha sonra yollayabilirsin. (a bit more formal/natural) Placing sonra at the very end (… yollayabilirsin sonra) is colloquial.

What exactly does -ebilirsin in yollayabilirsin mean—ability or permission?

It primarily expresses ability/possibility, but in context it often conveys permission (“you may/can send…”). Here, it clearly grants permission: send the others later if you like.

How would I say this more politely or formally?

Singular polite: Lütfen yalnızca gerekli dosyaları gönderir misiniz? Diğerlerini daha sonra gönderebilirsiniz.
Or: Lütfen yalnızca gerekli dosyaları gönderebilir misiniz? Using -ir misiniz? or -ebilir misiniz? sounds polite/formal, suitable for emails.

How do I address multiple people (or be polite) with the imperative?

Use the plural/polite forms:

gönderin (instead of gönder)
yollayabilirsiniz/gönderebilirsiniz (instead of yollayabilirsin/gönderebilirsin)

Is the comma without ve (“and”) normal in Turkish here?

Yes. Turkish often links two related clauses with just a comma when the subject is the same. You could add ve if you want (… gönder ve diğerlerini …), but it’s not necessary.

What’s the difference between gerekli and gereken (for “necessary/required”)?

gerekli = necessary, needed (adjective): gerekli dosyalar = the necessary files.
gereken = “that which is required” (participle): gereken dosyalar ≈ the files that are required. In many contexts, they’re interchangeable; gerekli is more purely adjectival.

Why does yollayabilirsin have a double L and a Y?

The verb is yolla- (with double L).
To add the ability suffix -(y)abil, a buffer y appears because the stem ends in a vowel: yolla + yabil + ir + sin → yollayabilirsin.

How would I say it using only gönder (no yolla)?

Totally fine:

Lütfen yalnızca gerekli dosyaları gönder, diğerlerini sonra gönderebilirsin. Same meaning, slightly more neutral/standard register.

Pronunciation tips for tricky parts?

ö in gönder is a rounded front vowel (like German ö): say a short “eu” as in French “deux,” but quick.
ğ in diğerlerini lengthens the preceding vowel and may create a slight glide; diğer sounds like “dee-er” (not a hard “g”).
Word stress: typically on the last syllable of verbs: göndeR, yollayabilirSIN.