أضع الكاميرا في الحقيبة قبل أن أخرج من البيت.

Because the verb itself already shows the subject. In أضع, the prefix أـ tells you the subject is I.

So أضع already means I put / I place.
If you add أنا, it becomes more emphatic or contrastive:

• أضع الكاميرا... = I put the camera...
• أنا أضع الكاميرا... = I put the camera... / As for me, I put the camera...

In normal MSA, leaving out the pronoun is very common.

That is a very normal Arabic sentence pattern. MSA often uses a verbal sentence, where the action comes first.

So:

• أضع الكاميرا في الحقيبة... is completely natural.
• You could also say أنا أضع الكاميرا في الحقيبة..., but that sounds more explicit or emphatic.

English usually requires the subject first, but Arabic often does not.

أضع means I put or I place. It comes from the root verb وضع.

This verb begins with و in the past tense, but in the present tense that initial و drops:

• وضع = he put
• يضع = he puts
• أضع = I put

So أضع is the expected present-tense form. This is a common pattern with some verbs whose first root letter is و.

Because في means in / inside, and that is the natural preposition after put when the result is that something ends up inside something else.

So:

• أضع الكاميرا في الحقيبة = I put the camera in the bag

By contrast, إلى usually means to / toward, focusing on direction rather than final location inside. With a container like a bag, في is the normal choice.

You could also hear:

• داخل الحقيبة = inside the bag

But في الحقيبة is the basic and natural expression.

قبل means before. When Arabic says before followed by a whole verb clause, it usually uses أن.

So:

• قبل أن أخرج = before I go out / before I leave

Compare that with a noun or verbal noun after قبل:

• قبل الخروج = before going out

So قبل أن + verb is a very common structure in MSA.

Yes. After أن, the verb is normally in the subjunctive in MSA.

In this sentence, the verb is still written أخرج, but in fully vocalized Arabic the ending changes:

• أخرجُ = I go out / I leave → indicative
• أخرجَ = that I go out / after أن → subjunctive

Because short vowels are usually not written in everyday Arabic text, both forms look the same on the page. So the mood change is real, even though the spelling usually does not visibly change.

Because the verb خرج normally uses من to show the place someone exits from.

So:

• أخرج من البيت = I go out of the house / I leave the house

The preposition من is important because it marks the starting point or source. This is similar to English out of.

The prefix الـ means the. These nouns are definite because the speaker is talking about specific, identifiable things:

• الكاميرا = the camera
• الحقيبة = the bag
• البيت = the house / the home

In context, this often means items already known to the speaker and listener, or simply the normal, specific objects involved in the situation.

If you wanted indefinite nouns, you could say:

• كاميرا = a camera
• حقيبة = a bag

If you wanted to make possession explicit, you could say:

• حقيبتي = my bag
• بيتي = my house / my home

الكاميرا is a borrowed word, but it is very common and fully usable in Arabic. Learners will see and hear it often.

It is generally treated as a feminine noun. So if you describe it with an adjective, the adjective is feminine too:

• كاميرا جديدة = a new camera
• الكاميرا الجديدة = the new camera

A more formal alternative is آلة التصوير, but كاميرا is extremely common.

It can mean either, depending on context.

• بيت can mean the physical house
• It can also mean home, especially when talking about going out, returning, staying at home, and so on

In this sentence, من البيت can naturally be understood as from the house or from home, depending on the translation style.

Another common word is المنزل, which often sounds a little more formal or literal for house/home. But البيت is very common and natural.

A fully vocalized version would be:

أضعُ الكاميرا في الحقيبةِ قبلَ أن أخرجَ من البيتِ.

The important things to notice are:

• أضعُ has the normal present-tense ending
• الحقيبةِ is after في, so it is in the genitive
• قبلَ is usually written with a final fatḥa in this structure
• أخرجَ is subjunctive after أن
• البيتِ is after من, so it is also in the genitive

In normal unvowelled writing, most of these endings are not shown, which is why learners often have to infer them from grammar.