Learn Hardcore Korean: jeomsimeun mwo sikillae? nan bibimbap sikilkka hae. - What shall we order for lunch? I’m thinking of ordering bibimbap.

It marks 점심 (lunch) as the topic: “As for lunch…”. It sets the frame for the discussion. You could drop it in speech and say 점심 뭐 시킬래? with little change in meaning. Don’t use the object marker here (✗ 점심을 뭐 시킬래?), because the object of “order” is “what,” not “lunch.”

Is 뭐 the same as 무엇 and 뭘?

뭐 is the most common casual form of “what.”
무엇 is the full/formal dictionary form.
뭘 = 무엇을 (object form). In speech you’ll hear both 뭐 시킬래? (particle dropped) and 뭘 시킬래? (object marked). 뭐를 is technically okay but sounds stiff or childlike; people prefer 뭘.

What exactly does the ending -(으)ㄹ래? in 시킬래? mean?

It asks about the listener’s preference or intention: “Would you like to… / Do you want to…?” So 뭐 시킬래? is “What do you want to order?” It’s casual; add 요 for polite: 뭐 시킬래요?

How is -(으)ㄹ래? different from -(으)ㄹ까? (e.g., 뭐 시킬까?)?

-(으)ㄹ래? asks the other person’s choice (you-focused).
-(으)ㄹ까? proposes a joint action (we-focused), like “Shall we…?”
So:
뭐 시킬래? = “What do you want to order?”
우리 뭐 시킬까? = “What shall we order?”

Who is the subject in 뭐 시킬래?—“you” or “we”?

Korean drops subjects when obvious. 뭐 시킬래? most naturally targets “you” (your choice). If you want to make it clearly inclusive, say 우리 뭐 시킬까?

What does 난 mean and how is it different from 나는 or 저는?

난 = contracted 나는 (“as for me”), casual.
나는 = full form, neutral/casual.
저는 = polite/deferential “I (topic).”
Match politeness:
Casual: 난 비빔밥 시킬까 해.
Polite: 저는 비빔밥 시킬까 해요.

Why is there no object particle after 비빔밥 (i.e., why not 비빔밥을 시킬까 해)?

In casual speech, object markers 을/를 are often dropped when the meaning is clear. Both are correct:

Natural speech: 비빔밥 시킬까 해.
More explicit: 비빔밥을 시킬까 해.

What does 시킬까 해 mean exactly?

-(으)ㄹ까 하다 expresses a tentative plan or consideration: “I’m thinking of ~ / I might ~.” 난 비빔밥 시킬까 해 softens the statement compared to a firm decision.

How does 시킬까 해 compare with 시킬래, 시킬게, 시키려고 해, and 시키고 싶어?

시킬까 해: I’m considering it; tentative.
시킬래: I want to / I’ll order (my preference).
시킬게: I’ll (go ahead and) order it (for you/our sake; commitment).
시키려고 해: I intend/plan to order (more decided).
시키고 싶어: I want to order (states desire).

Why use 시키다 and not 주문하다?

Both can mean “to order (food),” but:

시키다 is the everyday, colloquial choice with food/drinks.
주문하다 can sound a bit more formal or businesslike.
Either works in restaurants; 시키다 feels more casual.

Does 시키다 also mean “make someone do something”? Is that confusing?

Yes, 시키다 also means “to have someone do/to assign.” Context disambiguates:

Food context: 비빔밥을 시키다 = order bibimbap.
Task context: 그에게 일을 시키다 = make him do a task.
In your sentence, the food context makes it clear.

Can I say 먹을래 instead of 시킬래?

뭐 먹을래? = What do you want to eat? (general preference)
뭐 시킬래? = What do you want to order? (when ordering from a menu/delivery)
Both are fine at a restaurant. 먹다 is broader; 시키다 focuses on the act of ordering.

How polite is the original? How would I make a polite version?

Original is casual. Polite versions:

Friendly-polite: 점심은 뭐 시킬래요? 전 비빔밥 시킬까 해요.
More deferential (to seniors/customers):
- Asking preference to eat: 점심은 뭐 드실래요?
- From staff: 뭐 주문하시겠어요?
- Your reply (soft): 저는 비빔밥 시킬까 해요.

Why is there a space in 시킬까 해?

Because it’s the construction -(으)ㄹ까 하다 (a separate verb 하다 “to do”). Standard spacing is 시킬까 해. In texting, people often write 시킬까해, but the spaced form is the norm.

What’s the pronunciation like for these words?

뭐: “mwo” (close to “m-waw”).
시킬래: “shi-kil-lae” (the two ㄹ’s touch, sounding a bit long).
비빔밥: “bi-bim-bap” (final p is unreleased before a pause).
시킬까 해: spoken smoothly as “shi-kil-kka hae” (a crisp kk sound in -kka).

Is there a difference between writing 점심은 뭐 시킬래? and 점심 뭐 시킬래?

Both are common. 점심은 explicitly marks “lunch” as the topic; dropping 은 is fine in speech and sounds a bit snappier.

Could I say 우리 to make it clearly “we/us”?

Yes. For a joint decision, use -(으)ㄹ까? with 우리:

우리 점심 뭐 시킬까? = “What shall we order for lunch?”

How would a native naturally respond to 뭐 시킬래?

Common patterns:

State your choice: 난 비빔밥. / 난 비빔밥 시킬래.
Offer two options: 비빔밥이나 김치찌개 어떄?
Be tentative: 난 비빔밥 시킬까 해. 너는?
Defer: 아무거나 좋아. 네가 골라.

How do I add quantities when ordering?

Use counters:

비빔밥 두 개 시킬까 해. (two orders; 개 is common for menu items)
More “food-bowl” specific: 비빔밥 두 그릇 시킬까 해.
At Korean BBQ: 삼겹살 2인분 시킬까 해. (2 servings)

Is 시킬래? ever written as two words like “시킬 래?” or as “시켜래?”

No. The ending -래 attaches directly to the prospective stem (-ㄹ form): 시킬래? is correct. Don’t split it, and don’t say ✗시켜래.
Compare: 하다 → 할래?, 먹다 → 먹을래?, 가다 → 갈래?