Kan du göra det själv?

Because this is a yes/no question. In Swedish, yes/no questions usually put the finite verb first.

• Statement: Du kan göra det själv. = You can do it yourself.
• Question: Kan du göra det själv? = Can you do it yourself?

So the word order changes to show that it is a question.

Kan is the present tense of kunna, which means can / to be able to.

So Kan du ...? usually means Can you ...? or Are you able to ...?

Depending on tone and context, it can ask about:

• ability: Are you able to do it?
• possibility: Is it possible for you to do it?
• sometimes a polite request: Can you do it?

In this sentence, with själv, it often suggests Can you manage to do it on your own?

Because kan is a modal verb, and after modal verbs in Swedish, the next verb is usually in the infinitive.

So you get:

• kan göra = can do
• vill göra = want to do
• ska göra = will / am going to do
• måste göra = must do

So göra is correct here because it follows kan.

After modal verbs such as kan, vill, ska, måste, Swedish normally does not use att.

So:

• Jag kan göra det. = I can do it.
• not Jag kan att göra det

This is similar to English, where we say can do, not can to do.

Det means it here.

It refers to whatever task, action, or thing has already been mentioned or is understood from the situation.

For example:

• Kan du göra det själv? = Can you do it yourself?

Swedish det can correspond to English it or sometimes that, depending on context, but in this sentence it is the most natural match.

In this sentence, själv means by yourself / on your own, so Swedish can use själv by itself.

• Kan du göra det själv? = Can you do it yourself? / Can you do it on your own?

You use dig själv when you are the object of the verb, not the subject doing something alone.

For example:

• Du ser dig själv i spegeln. = You see yourself in the mirror.

So:

• själv = yourself, in the sense of on your own
• dig själv = yourself, when you are the object

Not exactly.

• själv focuses on doing something on your own / without help
• ensam focuses on being alone / without other people present

Compare:

• Kan du göra det själv? = Can you do it yourself? / Can you do it without help?
• Är du ensam? = Are you alone?

Sometimes the ideas overlap, but they are not interchangeable in every situation.

Yes, du is the normal Swedish word for you in the singular, and modern Swedish uses it in most situations, even with strangers.

Unlike many European languages, Swedish usually does not require a separate formal pronoun in everyday speech.

You may sometimes see Ni, but it is much less central than formal you forms in languages like German or French. For most learners, du is the standard and safest choice.

Yes, you can, but the emphasis changes.

• Kan du göra det själv?
  Focuses on doing it on your own

• Kan du själv göra det?
  Puts more emphasis on you personally, as opposed to someone else

So both are possible, but they are not exactly identical in nuance.

A rough pronunciation guide is:

• Kan ≈ kahn
• du ≈ dy with rounded lips
• göra ≈ YÖ-ra or YUR-a
  The g sounds like y before ö
• det is often pronounced more like de
• själv starts with the difficult Swedish sj sound, which has no exact English equivalent; a rough approximation is shelv or hwelv, depending on accent

A very rough full approximation could be:

kahn dy YÖ-ra de shelv

But this is only approximate. The hardest parts for English speakers are usually ö and the sj sound in själv.