אם אני לא קמה בזמן, תעירי אותי בבקשה בשש וחצי.

Because the sentence is addressed between females:

• אני לא קמה = I am not getting up / I don’t get up, said by a female speaker
• תעירי אותי = you wake me, said to a female listener

If the speaker were male, you would say קם instead of קמה:

• אם אני לא קם בזמן...

If the listener were male, you would say תעיר instead of תעירי:

• תעיר אותי בבקשה...

So Hebrew verbs often show gender very clearly.

Good question. For a future condition, many learners expect:

• אם לא אקום בזמן = if I don’t get up on time

That is absolutely correct.

But in everyday Hebrew, especially in speech, people also use the present form in this kind of situation:

• אם אני לא קמה בזמן

This can sound a bit more like:

• if I’m not getting up on time
• if I’m not up on time
• if I don’t manage to get up on time

So:

• אם לא אקום בזמן = more straightforward future
• אם אני לא קמה בזמן = very natural in speech, slightly more about the situation/state

Both are possible; this sentence uses a common colloquial pattern.

Formally, תעירי is the 2nd person feminine singular future form of להעיר = to wake someone up.

But in modern Hebrew, future forms are very often used to give commands or requests, especially in everyday speech. So here it functions like:

• Wake me up, please

There is also a true imperative form:

• העירי אותי

But in modern spoken Hebrew, the future form is usually more common and more natural:

• תעירי אותי sounds normal and everyday
• העירי אותי is grammatical, but less common in casual speech

Because the verb already tells you who the subject is.

תעירי already means you (feminine singular) will wake / wake. Hebrew often drops subject pronouns when they are not needed.

So:

• תעירי אותי = wake me up
• את תעירי אותי = you wake me up with extra emphasis, contrast, or emotion

The version without את is the normal one here.

Because אותי is the direct object form meaning me.

Compare:

• אני = I (subject)
• אותי = me (direct object)
• לי = to me / for me

The verb להעיר takes a direct object: you wake someone.

So:

• תעירי אותי = wake me up
• not תעירי אני
• not usually תעירי לי for this meaning

Also, you do not add a separate את before אותי, because אותי already contains that object-marker form historically.

Here בזמן means on time.

It is built from:

• ב־ = in / at / on
• זמן = time

So literally it is something like in time, but in this sentence the natural meaning is on time.

Examples:

• אני מגיע בזמן = I arrive on time
• היא לא קמה בזמן = she doesn’t get up on time

Hebrew often tells time this way:

• שש = six
• וחצי = and a half

So שש וחצי literally means six and a half, which is how Hebrew says six-thirty.

The ב־ at the beginning means at:

• בשש וחצי = at six-thirty

You do not need to say the word hour here. Just the number expression is enough.

בבקשה means please.

It makes the request softer and more polite:

• תעירי אותי = wake me up
• תעירי אותי בבקשה = please wake me up

Its position can move around a little:

• תעירי אותי בבקשה בשש וחצי
• בבקשה תעירי אותי בשש וחצי

Both are natural. In this sentence, putting בבקשה after אותי sounds very normal.

Literally, קמה comes from לקום, which means to get up / to rise / to stand up.

In context, with sleep and time, it usually means:

• get up
• sometimes loosely wake up, depending on context

So אם אני לא קמה בזמן is about not getting up at the right time. The second verb, תעירי, is more specifically wake me up.

That difference is common in Hebrew:

• לקום = to get up
• להתעורר = to wake up
• להעיר מישהו = to wake someone up

Yes. A few natural alternatives are:

• אם לא אקום בזמן, תעירי אותי בבקשה בשש וחצי.
• אם אני לא קמה בזמן, בבקשה תעירי אותי בשש וחצי.
• אם אני לא קמה בזמן, תעירי אותי בשש וחצי, בבקשה.

These all mean basically the same thing. The original sentence is perfectly natural; the alternatives mostly change style, emphasis, or how spoken it sounds.