Opłacę rachunki, a limit wydatków pomoże mi odkładać pieniądze.

Because Polish often drops subject pronouns when they are clear from the verb form.

• opłacę = I will pay
• The ending -ę already tells you the subject is I

So Opłacę rachunki naturally means I will pay the bills without needing ja.

You could say Ja opłacę rachunki, but that adds emphasis, like I will pay the bills.

Opłacę is a future-tense meaning form of a perfective verb.

In Polish, many perfective verbs use what looks like a present-tense form, but it actually refers to the future:

• opłacę = I will pay / I’ll settle
• not I pay

This happens because perfective verbs describe a completed whole action, and in Polish they do not have a true present-tense meaning.

Because rachunki is the accusative plural, which is used here as the direct object of the verb opłacę.

• singular: rachunek = bill
• plural nominative: rachunki
• plural accusative: rachunki

For this masculine inanimate noun, the accusative plural is the same as the nominative plural.

So:

• opłacę rachunki = I will pay the bills

By contrast, rachunków is usually genitive plural, used in other contexts.

Both can relate to paying, but opłacić rachunki is especially natural for settling bills.

A rough distinction:

• opłacić rachunki = to pay/settle bills, cover them
• zapłacić often focuses more generally on paying for something or paying an amount

In many situations they overlap, but with rachunki, opłacić is a very common and natural choice.

In Polish, a often links two clauses with a slight sense of contrast, shift, or separate parallel information.

So:

• Opłacę rachunki, a limit wydatków pomoże mi odkładać pieniądze.

means something like:

• I’ll pay the bills, and as for the spending limit, it will help me save money.

If you used i, it would sound more like a simple addition:

• X and Y

But a is very common when moving from one idea to another related one. English often still translates both as and, depending on context.

Wydatków is genitive plural after the noun limit.

This is a very common Polish structure:

• limit czego? = a limit of what?
• limit wydatków = spending limit / limit of expenses

So:

• limit = limit
• wydatki = expenses
• wydatków = of expenses

English often uses a noun directly before another noun, but Polish commonly uses a noun + genitive structure instead.

Mi means to me and is the dative form of ja.

The verb pomóc / pomagać takes the person being helped in the dative:

• pomóc komu? = to help whom?
• pomoże mi = it will help me

So the structure is:

• limit wydatków pomoże mi odkładać pieniądze
• the spending limit will help me save/put aside money

Both forms can mean me, but they are used differently.

• mi = the usual short, unstressed dative form
• mnie = the fuller form, often used for emphasis, contrast, or after certain prepositions

Here, there is no special emphasis, so mi is the normal choice:

• pomoże mi = natural
• pomoże mnie = incorrect here
• pomoże mnie? no, because the dative full form would be mnie, but after pomóc the normal neutral word is still mi, and mnie would only appear in emphatic contexts

For example:

• Mnie to nie pomoże = That won’t help me
  (emphatic)

But in the sentence you gave, mi is the natural form.

Because after pomoże mi..., the sentence is talking about an ongoing habit or repeated activity: saving money over time.

• odkładać = imperfective = to be putting aside, to save regularly
• odłożyć = perfective = to put aside once / to set aside completely

So:

• pomoże mi odkładać pieniądze = will help me save money / put money aside regularly

If you used odłożyć, it would sound more like helping with a single completed act, which is not the main idea here.

They are close, but not always identical.

• odkładać pieniądze = to put money aside
• oszczędzać pieniądze = to save money

Odkładać often suggests setting money aside bit by bit, while oszczędzać can also mean being economical / spending less.

In this sentence, odkładać pieniądze works very well because a spending limit helps you put money aside regularly.

Yes, but Polish treats pieniądze as a plural-only noun in normal usage.

So:

• pieniądze = money
• grammatically plural, even though in English money is singular/uncountable

That is why Polish says things like:

• te pieniądze = this money / these funds
• mam pieniądze = I have money

This is something you usually just have to learn as a vocabulary fact.

The structure is:

• limit wydatków = subject
• pomoże = verb
• mi = indirect object in the dative
• odkładać pieniądze = infinitive phrase showing what it will help me do

So literally it is:

• The spending limit will help me to put aside money

This kind of structure is common in Polish:

• [something] pomoże mi [infinitive]
• [something] will help me [do something]

Yes. Pomoże comes from the perfective verb pomóc, so its present-looking form has future meaning:

• pomoże = will help

So both main verbs in the sentence are future in meaning:

• opłacę = I will pay
• pomoże = will help

Yes, Polish word order is fairly flexible, although some orders sound more natural than others.

The original:

• Opłacę rachunki, a limit wydatków pomoże mi odkładać pieniądze.

is neutral and natural.

You could rearrange parts for emphasis, for example:

• Limit wydatków pomoże mi odkładać pieniądze.
• Mi pomoże limit wydatków odkładać pieniądze.
  This is much more marked and less neutral.

So yes, word order can change, but the original sentence is a good standard model for learners.

Yes. The letter ę is one of the Polish nasal vowels, but in real speech its pronunciation can vary depending on position.

A simple learner-friendly guide:

• in opłacę, the final ę is often pronounced less strongly nasal than learners expect
• in pieniądze, the pronunciation is influenced by the following consonants, so it may not sound like a pure nasal vowel

The most important thing at first is:

• recognize ę in spelling
• listen to native recordings
• don’t worry if your first attempts are not perfect

Pronunciation details here are useful, but they are less important than understanding the grammar and vocabulary first.