Learn Hardcore Russian: Завтра я поеду в город на собеседование. - Tomorrow I will go to the city for an interview.

In the sentence, поеду is the 1st person singular future form of поехать. It means I will go / I will set off (by vehicle), usually one specific trip.

If you said:

Я еду в город – I am going to the city (now).
Я езжу в город – I go to the city (regularly / habitually).
Завтра я поеду в город – Tomorrow I will go to the city (one specific trip).

So поеду matches the idea of a single planned future trip.

Why is it поеду, not буду ехать?

Both are grammatically possible, but they have different nuances:

Завтра я поеду в город…
Focuses on the fact of the trip happening. Neutral way to state a plan or decision.
Завтра я буду ехать в город…
Focuses on the process of “being in transit” at some time tomorrow: At some point tomorrow, I will be in the middle of going to the city.

In most cases when you simply say what you will do tomorrow, Russians prefer the perfective future: я поеду.
Буду ехать is used when you want to emphasize the duration/process (for example, if someone asks “What will you be doing at 3 pm tomorrow?”).

Is поеду present or future tense?

Grammatically, поеду is a future tense form.

Perfective verbs in Russian (like поехать) do not have a true present tense. Their “present” endings actually refer to the future:

я поеду – I will go
ты поедешь – you will go
он поедет – he will go

So whenever you see a perfective verb like поеду, сделаю, куплю etc., it refers to the future, not the present.

Why is it в город and not в городе?

This is about case and direction vs location:

в город – accusative case → motion to the city
в городе – prepositional case → location in the city

In the sentence, you are going to the city, so Russian uses в + accusative: в город.

Also, город is a masculine inanimate noun. For such nouns, the accusative singular = nominative singular, so it stays город, not города or городе.

Why do we say в город, but на собеседование? How do I know when to use в vs на?

Here the choice is mostly lexical (fixed usage), but there is a pattern:

в
- accusative – usually into a place / space
- в город – to the city
- в школу – to school (as a building/place)
- в театр – to the theater
на
- accusative – often onto a surface or to an event / activity / institution
- на собеседование – to an interview (event)
- на концерт – to a concert
- на работу – to work
- на лекцию – to a lecture

An interview is treated as an event, so Russian uses на: на собеседование.

Why is it на собеседование and not на собеседовании?

This is again direction vs location:

на собеседование – accusative, motion to the interview
- I am going *to an interview.*
на собеседовании – prepositional, location at the interview
- I am *at the interview.*

In the sentence, you are traveling to the interview, not describing where you are at the moment, so на собеседование is correct.

What case is собеседование in, and why doesn’t it change form?

In на собеседование, the noun собеседование is in the accusative case (after на with motion).

Собеседование is neuter, inanimate. For neuter inanimate nouns, the accusative singular = nominative singular, so:

Nominative: собеседование
Accusative: собеседование

The ending doesn’t change, even though the case has changed.

Can I change the word order, for example: Я поеду завтра в город на собеседование?

Yes. Russian word order is quite flexible. All of these are grammatically correct:

Завтра я поеду в город на собеседование.
Я завтра поеду в город на собеседование.
Я поеду завтра в город на собеседование.

They all mean the same in everyday speech. The differences are only in subtle emphasis:

Завтра я поеду… – light emphasis on tomorrow.
Я завтра поеду… – more neutral, everyday style.
Я поеду завтра… – slight emphasis on I will go (not someone else).

The phrase в город на собеседование is usually kept together at the end, but you could move завтра and я fairly freely.

Do we really need the pronoun я here, or can we drop it?

You can drop it:

Завтра поеду в город на собеседование.

This is perfectly natural in Russian, because the verb ending -у in поеду already shows it is I (1st person singular).

Using я is also normal. It can sound a bit more explicit or contrastive (I will go, as opposed to someone else), but in many cases it’s just neutral. Both versions are fine.

Why is there no word for “the” in в город or на собеседование?

Russian has no articles at all. There is no direct equivalent of “a / an / the”.

Whether English uses a or the is understood from context in Russian:

в город can mean to the city or to a city / into town.
на собеседование can mean to the interview (a known one) or to an interview (some interview).

Only the surrounding context tells you whether English would use a or the.

What exactly does город mean here: the city, a city, or town?

Город basically means city / town. In this sentence, typical interpretations are:

If you are in a village / countryside, в город often means into town (the nearest city).
If context is clear (both speakers know which city), it is understood as to the city (that particular city).
Without context, it can be translated simply as to the city or to town, depending on what sounds more natural in English.

Because Russian has no articles, город stays the same form; the exact English equivalent (the city, a city, town) depends on context.

Could I say на интервью instead of на собеседование?

You can hear на интервью, but there is a nuance:

Собеседование is the standard word for a job interview (or entrance interview, visa interview, etc.).
Интервью usually means an interview in media (TV, newspaper, podcast), although some speakers do use it for job interviews too, influenced by English.

If you want natural, neutral Russian for a job interview, на собеседование is the best choice.

How would I say that I go there regularly, not just once?

To talk about regular / repeated trips, Russians use the multi-directional imperfective verb ездить:

Я часто езжу в город на собеседования.
I often go to the city for interviews.
Я каждый месяц езжу в город на собеседование.
I go to the city for an interview every month.

In your original sentence with завтра, we talk about one specific trip tomorrow, so the perfective поеду is appropriate:
Завтра я поеду в город на собеседование.

Why do we use поеду (by vehicle) and not пойду (on foot)?

Russian distinguishes motion on foot and by vehicle:

идти / ходить / пойти – to go on foot
ехать / ездить / поехать – to go by vehicle (car, bus, train, etc.)

Поеду clearly implies that you will travel by some vehicle.
If you really meant you will walk to the city for the interview, you would say:

Завтра я пойду в город на собеседование.

But in normal situations, going to the city implies using a vehicle, so поеду is the natural verb.

Where is the stress in the words of this sentence, and how is it roughly pronounced?

Stresses (marked with an accent):

за́втра – ZA-vtra
я́ – YA (usually unstressed in running speech, but can carry stress if emphasized)
пое́ду – pa-YE-du
го́род – GO-rat (final д is often devoiced: [t])
собесе́дование – sa-bi-SYE-da-va-ni-ye

Whole sentence (stresses):
За́втра я пое́ду в го́род на собесе́дование.

You don’t need perfect phonetics right away, but knowing where the stress falls helps with understanding and being understood.