ऑफिस जाने से पहले मैं माँ से मिलूँगी, और घर आने के बाद मैं हिंदी पढ़ूँगी।

Because after expressions like से पहले and के बाद, Hindi usually uses the oblique infinitive form of the verb.

• जाना → जाने
• आना → आने

So:

• ऑफिस जाने से पहले = before going to the office
• घर आने के बाद = after coming home

This is a very common pattern in Hindi:

• खाने से पहले = before eating
• सोने के बाद = after sleeping

So a good rule is: when a verb comes before a postposition in this kind of time expression, it often changes from -ना to -ने.

These are just standard fixed expressions in Hindi:

• से पहले = before
• के बाद = after

So you say:

• जाने से पहले
• आने के बाद

This is not something you usually build logically word-by-word as a beginner; it is best learned as a chunk.

A few more examples:

• खाना खाने से पहले = before eating food
• काम करने के बाद = after doing work

So the most natural way to remember this is:

• Verb + ने + से पहले
• Verb + ने + के बाद

The verb मिलना in the sense of to meet someone commonly takes से.

So:

• मैं माँ से मिलूँगी = I will meet mother

This is different from English, where we say meet someone without a preposition. In Hindi, the person you meet is usually marked with से.

Examples:

• मैं दोस्त से मिलूँगा। = I will meet a friend.
• वह शिक्षक से मिलेगी। = She will meet the teacher.

So for English speakers, this is an important pattern to memorize:

• X से मिलना = to meet X

The ending -ूँगी shows:

• future tense
• first person singular (I)
• feminine speaker

So मैं मिलूँगी and मैं पढ़ूँगी mean I will meet and I will study/read, said by a female speaker.

Compare:

• feminine: मैं मिलूँगी / पढ़ूँगी
• masculine: मैं मिलूँगा / पढ़ूँगा

So the sentence tells us that the speaker is female.

Only the future verb endings would change:

• मिलूँगी → मिलूँगा
• पढ़ूँगी → पढ़ूँगा

So it would become:

ऑफिस जाने से पहले मैं माँ से मिलूँगा, और घर आने के बाद मैं हिंदी पढ़ूँगा।

Everything else stays the same.

Yes, Hindi could leave it out if the subject is clearly the same.

Your sentence says:

ऑफिस जाने से पहले मैं माँ से मिलूँगी, और घर आने के बाद मैं हिंदी पढ़ूँगी।

You could also say:

ऑफिस जाने से पहले मैं माँ से मिलूँगी, और घर आने के बाद हिंदी पढ़ूँगी।

Both are natural. Repeating मैं can make the sentence clearer or more balanced, especially in a learner-friendly or careful style.

So:

• with repeated मैं = a bit more explicit
• without repeated मैं = also normal if the subject is obvious

Hindi normally follows Subject–Object–Verb word order.

So:

• मैं हिंदी पढ़ूँगी
  • मैं = subject
  • हिंदी = object
  • पढ़ूँगी = verb

This is different from English, which usually uses Subject–Verb–Object:

• I will study Hindi

In Hindi, the verb usually comes at the end of the clause.

More examples:

• मैं किताब पढ़ूँगी। = I will read a book.
• वह खाना खाएगा। = He will eat food.

It can mean either, depending on context. With a language like हिंदी, पढ़ना often means to study.

So:

• मैं हिंदी पढ़ूँगी usually means I will study Hindi

But in other contexts, पढ़ना can also mean to read:

• मैं किताब पढ़ूँगी। = I will read a book.

So पढ़ना is a broad verb covering both read and study in many situations.

Hindi often expresses going to a place without a separate word corresponding exactly to English to, especially with common destinations.

So:

• ऑफिस जाना = to go to the office
• घर आना = to come home

Hindi does have postpositions like को and में, but with motion verbs the structure is often different from English.

For everyday destinations, Hindi frequently just uses:

• place + जाना
• place + आना

Examples:

• स्कूल जाना = to go to school
• घर आना = to come home
• बाज़ार जाना = to go to the market

So ऑफिस जाने से पहले is perfectly normal.

In this expression, से is part of the fixed phrase से पहले meaning before.

So in:

• ऑफिस जाने से पहले

you should understand the whole unit जाने से पहले as before going.

It is better not to translate the से on its own too literally here. It is just part of the standard time expression.

Similarly:

• खाने से पहले = before eating
• निकलने से पहले = before leaving

Here के is part of the fixed phrase के बाद meaning after.

So:

• घर आने ke बाद = after coming home

Like से पहले, this is best learned as a chunk:

• Verb + ने + के बाद = after doing something

Examples:

• खाने के बाद = after eating
• काम करने के बाद = after working / after doing the work

So के here is not something you need to translate separately as a beginner; it is just part of the normal structure.

Yes. Hindi uses आना because the action is viewed relative to the speaker’s or narrative point of reference.

• घर आना = to come home
• घर जाना = to go home

In many contexts, English also says come home, so घर आने के बाद is very natural.

If the speaker wanted a different perspective, Hindi could use घर जाने के बाद, but that would sound more like after going home. In your sentence, घर आने के बाद is the most natural choice.

The sign ूँ shows a long ū sound with nasalization.

So:

• मिलूँगी sounds roughly like mi-LOON-gee, with the oo slightly nasalized
• पढ़ूँगी sounds roughly like pa-RHOON-gee, again with nasalization

A few helpful points:

• ऊ = long oo sound
• ँ adds nasalization
• गी is the feminine future ending here

So -ूँगी is a very common feminine future ending for मैं with many verbs:

• करूँगी = I will do
• जाऊँगी = I will go
• लिखूँगी = I will write

The sentence you have is natural, but Hindi word order is somewhat flexible as long as the relationships stay clear.

Original:

• ऑफिस जाने से पहले मैं माँ से मिलूँगी, और घर आने के बाद मैं हिंदी पढ़ूँगी।

You could also say:

• मैं ऑफिस जाने से पहले माँ से मिलूँगी, और घर आने के बाद हिंदी पढ़ूँगी।

This is also natural.

What usually stays true is:

• the verb tends to come near the end of each clause
• the time phrase can often move earlier for emphasis

So the order is flexible, but not completely random.

Yes. और is the normal everyday word for and in this kind of sentence.

So:

• ..., और ... = ..., and ...

It connects the two clauses naturally:

• first action/time frame
• second action/time frame

Very common examples:

• मैं चाय पीऊँगी और फिर काम करूँगी।
• वह आएगा और हम बात करेंगे।

So और is exactly what you would expect here.