yeonseup deokbune haendeureul jal sayonghaessseupnida.

덕분에 means thanks to or due to, and it usually suggests that the result is positive.

So in 연습 덕분에, the speaker is saying that practice helped produce a good result.

Compare:

• 연습 덕분에 = thanks to practice
• 연습 때문에 = because of practice

The second one is grammatically possible, but 때문에 is more neutral and is often used when the result is negative or just factual. Because 핸들을 잘 사용했습니다 is a good outcome, 덕분에 fits better.

Because 덕분에 attaches directly to the noun.

So:

• 연습 덕분에 = thanks to practice

You do not say:

• 연습을 덕분에
• 연습이 덕분에

Here, 덕분에 works like a postposition attached to the noun phrase before it.

Korean very often leaves out the subject when it is clear from context.

So 연습 덕분에 핸들을 잘 사용했습니다 can naturally mean:

• I used the handle well thanks to practice.
• We used the handle well thanks to practice.
• He/She used the handle well thanks to practice.

In real Korean, the listener usually figures out the subject from the situation. English needs the subject more often, but Korean often does not.

If you wanted to include it, you could say something like:

• 저는 연습 덕분에 핸들을 잘 사용했습니다.

But leaving it out is very normal.

핸들 is a loanword from English handle, but in Korean its meaning depends on context.

It can refer to things like:

• a steering wheel
• a handle
• sometimes a control device shaped like a wheel

In many everyday contexts, 핸들 often means steering wheel.

So the exact meaning depends on what the speaker is talking about. Even though the word came from English, you should not assume it always matches English usage perfectly.

Because 핸들 is the direct object of the verb 사용했습니다.

• 핸들 = the object being used
• 을/를 = object marker

Since 핸들 ends in a consonant sound, it takes 을, not 를:

• 핸들 + 을 → 핸들을

This is the standard object marking pattern in Korean.

잘 is an adverb meaning well.

It modifies the verb 사용했습니다, not the noun 핸들.

So:

• 잘 사용했습니다 = used well

This is different from English, where learners sometimes expect something closer to good. In Korean, when you want to say someone does an action well, you usually use the adverb 잘 before the verb.

Examples:

• 잘 먹어요 = eats well
• 잘 해요 = does it well
• 잘 사용했습니다 = used it well

사용했습니다 is the past tense, formal polite form of 사용하다, which means to use.

Breakdown:

• 사용하다 = to use
• 사용했- = used
• 습니다 = formal polite ending

So 사용했습니다 means used in a formal, polite style.

Related forms:

• 사용했습니다 = formal polite
• 사용했어요 = polite, less formal
• 사용했다 = plain style

This sentence sounds like something you might hear in a presentation, report, interview, or careful speech.

It is grammatically correct, but whether it sounds most natural depends on what 핸들 means in context.

If 핸들 means a physical handle or steering wheel, Korean often uses more specific verbs such as:

• 잡다 = hold
• 돌리다 = turn
• 다루다 = handle, control
• 조작하다 = operate, manipulate

So if the meaning is specifically about controlling a steering wheel, something like this may sound more natural:

• 연습 덕분에 핸들을 잘 다뤘습니다.

If the point is simply used, then 사용했습니다 is fine. It is just a bit broader and more general.

Yes, it can.

Normally 덕분에 is positive and appreciative, but in conversation people sometimes use it sarcastically, especially with tone of voice.

For example:

• 너 덕분에 늦었어.

Literally this looks like I was late thanks to you, but depending on tone it can mean something more like Because of you, I was late.

In your sentence, though, there is no sign of sarcasm. It sounds sincerely positive.

This is a very normal order.

• 연습 덕분에 = reason/cause
• 핸들을 = object
• 잘 사용했습니다 = adverb + verb

Korean word order is somewhat flexible, but this sentence follows a very common pattern:

reason + object + adverb + verb

Since Korean verbs come at the end, the sentence naturally builds toward the main action.

A different order may still be possible in some contexts, but the given order is the most straightforward and natural for a learner to remember.