Muszę załatwić wizytę u lekarza na piątek.

Muszę means I must or I have to.

It comes from the verb musieć = to have to / must.

The ending -ę marks 1st person singular in the present tense, so:

• muszę = I must
• musisz = you must
• musi = he/she/it must

So the sentence starts with Muszę... = I have to...

After muszę, Polish usually uses an infinitive, just like English often uses must + verb or have to + verb.

So:

• Muszę załatwić = I have to arrange / take care of
• literally: I must arrange

This is a very common pattern in Polish:

• Muszę iść = I have to go
• Muszę zadzwonić = I have to call
• Muszę załatwić = I have to arrange / sort out

Załatwić is a very useful Polish verb with a broad meaning. Depending on context, it can mean:

• to arrange
• to sort out
• to take care of
• to get something done

In this sentence, załatwić wizytę means something like:

• to arrange an appointment
• to get an appointment sorted out

It is a perfective verb, so it suggests completing the task successfully.

Because wizyta is the direct object of załatwić, it has to be in the accusative case.

• nominative: wizyta = visit / appointment
• accusative: wizytę

So:

• załatwić wizytę = to arrange an appointment

This is very common in Polish: many verbs require the direct object in the accusative.

U lekarza means with the doctor, at the doctor’s, or to see the doctor, depending on context.

The preposition u is often used when talking about being at someone’s place, with a professional, or in someone’s care/service.

Examples:

• u dentysty = at the dentist’s
• u fryzjera = at the hairdresser’s
• u lekarza = at the doctor’s / with the doctor

So wizyta u lekarza means an appointment with the doctor.

Because the preposition u requires the genitive case.

So:

• nominative: lekarz = doctor
• genitive: lekarza

That is why we say:

• u lekarza
• u dentysty
• u nauczyciela

This is one of the things English speakers need to get used to: in Polish, prepositions often force a noun into a specific case.

This is a very important difference.

• na piątek means for Friday
• w piątek means on Friday

In this sentence, the idea is that the appointment is being arranged for Friday, so na piątek is the natural choice.

Compare:

• Muszę załatwić wizytę na piątek. = I need to arrange an appointment for Friday.
• Mam wizytę w piątek. = I have an appointment on Friday.

So na piątek is used when setting, booking, or planning something for that day.

No. A very common alternative is umówić wizytę.

For example:

• Muszę umówić wizytę u lekarza na piątek.

This often sounds a bit more specifically like to book / schedule an appointment.

The difference is roughly:

• załatwić wizytę = arrange / sort out an appointment
• umówić wizytę = book / schedule an appointment

Both can work, but umówić wizytę is often the more standard phrase for medical appointments.

Polish does not have articles like English a/an/the.

So wizytę can mean:

• an appointment
• the appointment

The exact meaning depends on context.

That means:

• Muszę załatwić wizytę u lekarza na piątek. could be understood as
• I need to arrange a doctor’s appointment for Friday or
• I need to arrange the doctor’s appointment for Friday

Usually the situation makes it clear.

Yes. Polish word order is more flexible than English word order because case endings show the grammatical roles.

The basic sentence:

• Muszę załatwić wizytę u lekarza na piątek.

But you could also hear variations such as:

• Na piątek muszę załatwić wizytę u lekarza.
• Muszę na piątek załatwić wizytę u lekarza.

These versions shift the emphasis slightly. For example:

• Na piątek at the beginning emphasizes the day: For Friday, I need to arrange...

Even though word order can move around, the original version sounds natural and neutral.

It can mean both, depending on context.

In everyday Polish, wizyta u lekarza is very commonly understood as a doctor’s appointment.

So while the literal meaning of wizyta is visit, in many situations the natural English translation is appointment.

For example:

• Mam wizytę u dentysty. = I have a dentist appointment.
• literally: I have a visit with the dentist.

This is very normal in Polish.

Yes, it matters.

Załatwić is perfective, which means it focuses on the action as completed.

Its imperfective partner is usually załatwiać.

Compare:

• Muszę załatwić wizytę. = I need to get the appointment arranged.
• Załatwiam wizytę. = I am arranging the appointment / I’m in the process of sorting it out.

In your sentence, załatwić is used because the speaker is talking about the need to successfully arrange the appointment, not just be busy arranging it.