मैं बैंक में पैसा जमा करती हूँ।

में is the postposition that usually means in, inside, or sometimes at a place.

So:

• बैंक = bank
• बैंक में = in the bank / at the bank

In this sentence, it marks the location where the depositing happens.

A native English speaker may expect a preposition before the noun, but Hindi uses postpositions, which come after the noun instead.

पैसा here means money in a general, uncountable sense. It does not have to mean a single coin.

So in this sentence:

• पैसा जमा करना = to deposit money

You can also hear पैसे in real life, and that is very common too:

• मैं बैंक में पैसे जमा करती हूँ।

That would also mean I deposit money in the bank.

Very roughly:

• पैसा = money as a general concept
• पैसे = money/funds/cash in a more everyday plural form

Both can work, depending on style and context.

जमा करना is a very common Hindi verb phrase meaning:

• to deposit
• to collect
• to save up
• to accumulate

In banking contexts, it usually means to deposit.

This is a compound expression:

• जमा = deposited / collected / accumulated
• करना = to do

Together, जमा करना functions like a single verb: to deposit.

So:

• पैसा जमा करना = to deposit money

Because the speaker is understood to be female.

In the present habitual, the verb agrees with the subject मैं in gender and number:

• मैं ... करता हूँ = I do ... (male speaker)
• मैं ... करती हूँ = I do ... (female speaker)

So this sentence is said by a woman or girl:

• मैं बैंक में पैसा जमा करती हूँ।

If a man were speaking, it would be:

• मैं बैंक में पैसा जमा करता हूँ।

This is how Hindi normally forms the present habitual.

Structure:

• verb stem + habitual participle + होना auxiliary

Here that gives:

• करती = habitual feminine singular form of करना
• हूँ = am

So जमा करती हूँ literally works like do deposit / am accustomed to depositing, but in natural English it is simply:

• I deposit
• I usually deposit
• I do deposit

The हूँ is an important part of the standard full form.

No. It is simple present / habitual present, not present continuous.

मैं बैंक में पैसा जमा करती हूँ। means something like:

• I deposit money in the bank
• I usually deposit money in the bank
• I deposit money at the bank

If you want I am depositing money in the bank, Hindi would normally use the continuous:

• मैं बैंक में पैसा जमा कर रही हूँ।
  (female speaker)

For a male speaker:

• मैं बैंक में पैसा जमा कर रहा हूँ।

So:

• करती हूँ = habitual / regular action
• कर रही हूँ = action happening right now

Because Hindi does not have articles like a, an, and the.

So बैंक can mean:

• a bank
• the bank

The exact meaning depends on context.

That is very normal in Hindi. Learners often want to insert an article somehow, but Hindi simply does not require one.

Because पैसा here is a direct object, and direct objects in Hindi are not always marked with को.

The marker को is often used with:

• specific people
• animate objects
• certain definite or affected objects

But with a general thing like money, Hindi usually just says:

• पैसा जमा करती हूँ

not

• पैसा को जमा करती हूँ ✘

So in this sentence:

• पैसा = direct object
• no को needed

Hindi usually prefers Subject – Object – Verb, with extra phrases like location placed before the verb as well.

This sentence is:

• मैं = subject
• बैंक में = location
• पैसा = object
• जमा करती हूँ = verb

So the full order is:

• I + in the bank + money + deposit

That may feel unusual to an English speaker, but it is normal in Hindi because the main verb usually comes at the end.

Also, Hindi word order is somewhat flexible. For example, these can also be natural depending on emphasis:

• मैं पैसा बैंक में जमा करती हूँ।
• मैं बैंक में पैसे जमा करती हूँ।

The original sentence is perfectly normal.

No. मैं always means I, regardless of gender.

The gender is shown by the verb form:

• मैं ... करता हूँ = male speaker
• मैं ... करती हूँ = female speaker

This is very common in Hindi: the pronoun itself does not change, but the verb often does.

Yes, depending on context.

जमा करना can mean:

• deposit
• save up
• collect
• accumulate

So if someone says:

• मैं पैसा जमा करती हूँ

it could sometimes mean I save money.

But because this sentence includes बैंक में, the banking meaning becomes much clearer:

• I deposit money in the bank

So the context strongly points to deposit, not just save up in general.

Either can work in English, depending on context.

Hindi में literally means in, so a very close translation is:

• in the bank

But natural English often says:

• at the bank

especially when talking about where an action happens.

So this Hindi sentence could correspond to either:

• I deposit money in the bank.
• I deposit money at the bank.

The exact English choice depends on style, not on a major grammar difference in Hindi.