לפני שאני שולחת אימייל רשמי לעירייה, אני רוצה לבדוק שכל הפרטים נכונים.

Because the speaker is female. In Hebrew, verbs in the present tense agree with the gender and number of the subject.

• אני שולחת = I send / I am sending (said by a woman)
• אני שולח = I send / I am sending (said by a man)

So if a male speaker said this sentence, it would begin:

לפני שאני שולח אימייל רשמי לעירייה...

Hebrew often repeats the subject pronoun when starting a new clause, even if English might not repeat I as naturally.

Here the sentence has two parts:

• לפני שאני שולחת אימייל רשמי לעירייה = Before I send an official email to the municipality
• אני רוצה לבדוק... = I want to check...

The second אני is not unusual or redundant in Hebrew. It sounds natural and clear.

In Hebrew, לפני ש... is a very common way to say before ... followed by a clause.

• לפני = before
• ש = that / which / introducing a clause
• אני שולחת = I send / I am sending

So לפני שאני שולחת means before I send.

This is just standard Hebrew structure. English does not usually say before that I send, but Hebrew does use this kind of connector.

Hebrew present tense often covers meanings that English expresses with several different forms, including simple present and near-future ideas, depending on context.

So:

• לפני שאני שולחת literally looks like before I am sending
• but naturally means before I send

Hebrew does this a lot with time words and clause markers. The tense is interpreted from the context, not just from the verb form alone.

לעירייה means to the municipality / to city hall / to the local council, depending on context.

It is made from:

• ל־ = to
• עירייה = municipality / city council / city hall

So:

• אימייל רשמי לעירייה = an official email to the municipality

A learner should also notice that ל attaches directly to the noun as a prefix.

Because רשמי is an adjective, and it must agree with אימייל in gender and number.

• אימייל is treated as masculine singular
• so the adjective is רשמי = masculine singular

Compare:

• אימייל רשמי = an official email
• הודעה רשמית = an official message
  because הודעה is feminine singular

So the adjective changes to match the noun it describes.

Because Hebrew commonly uses רוצה + infinitive to mean want to + verb.

• רוצה = want (here: feminine singular)
• לבדוק = to check

So:

• אני רוצה לבדוק = I want to check

This is very similar to English structure.

If the speaker were male, it would be:

• אני רוצה לבדוק for a female speaker
• אני רוצה לבדוק for a male speaker too?
  Not quite: the visible difference is in רוצה pronunciation and sometimes spelling context, but in unpointed Hebrew the written form is often the same. More fully:
  • female: אני רוצה
  • male: אני רוצה

In standard unpointed spelling, both are written the same, but they are pronounced differently:

• female: rotzá
• male: rotzé

Here שכל means that all or more naturally that all the...

It is made of:

• ש־ = that
• כל = all

So:

• אני רוצה לבדוק שכל הפרטים נכונים
• literally: I want to check that all the details are correct

This is a very common Hebrew structure.

Because when Hebrew says all the details, it often uses כל + definite noun:

• כל הפרטים = all the details

Without ה־, כל פרטים would sound unnatural here.

This is a useful pattern to remember:

• כל האנשים = all the people
• כל הספרים = all the books
• כל הפרטים = all the details

Because it agrees with הפרטים, which is masculine plural.

• הפרטים = the details (masculine plural)
• נכונים = correct (masculine plural)

So Hebrew makes the adjective match the noun.

Compare:

• הפרט נכון = the detail is correct
• הפרטים נכונים = the details are correct
• הכתובת נכונה = the address is correct
  because כתובת is feminine singular

In Hebrew present-tense sentences, there is usually no separate word for is / are.

So:

• כל הפרטים נכונים
• literally: all the details correct
• naturally: all the details are correct

So נכונים is an adjective, but in the sentence it works as the predicate, where English would use are.

This is extremely common in Hebrew:

• הבית גדול = the house is big
• הילדים עייפים = the children are tired
• הפרטים נכונים = the details are correct

Yes. In everyday Hebrew, you may also hear:

• מייל
• דוא״ל in more formal or official language

So possible alternatives are:

• לפני שאני שולחת מייל רשמי לעירייה...
• לפני שאני שולחת דוא״ל רשמי לעירייה...

But אימייל is very common and natural in modern spoken and written Hebrew.

The sentence is built like this:

• לפני ש... = before...
• clause 1: אני שולחת אימייל רשמי לעירייה
• main clause: אני רוצה לבדוק
• object clause: שכל הפרטים נכונים

So the full structure is:

Before I send an official email to the municipality, I want to check that all the details are correct.

This kind of multi-clause sentence is very typical of natural Hebrew, and each connector is worth learning:

• לפני ש... = before...
• ש... = that...