Если не автобусом, то на метро я всё равно доеду до работы вовремя.

These are two different common ways Russian expresses means of transport.

• автобусом is the instrumental case and means by bus
• на метро uses на + prepositional and means by metro / by subway

Both patterns are normal in Russian, but different transport words tend to prefer different expressions.

For example:

• ехать автобусом / ехать на автобусе = to go by bus
• ехать на метро = to go by metro

With метро, Russian normally says на метро, not метром.

Also, метро is an indeclinable noun, so its form does not change. That is why it stays метро after на.

Yes, absolutely. Если не на автобусе, то на метро is also natural.

Russian often allows both:

• автобусом
• на автобусе

Both mean by bus.

The version in your sentence, если не автобусом, sounds a bit more compact and neat in this contrast pattern:

• если не автобусом, то на метро

It has a slightly more streamlined, matter-of-fact feel.

Because Russian often omits repeated words when the meaning is obvious.

The full idea could be something like:

• Если не поеду автобусом, то на метро я всё равно доеду до работы вовремя.
• Если не доберусь автобусом, то на метро я всё равно доеду до работы вовремя.

But Russian very naturally shortens this to:

• Если не автобусом, то на метро...

English does something similar:

• If not by bus, then by metro...

So this is an example of ellipsis: the verb is understood and left out.

This is the standard if ..., then ... pattern.

• если = if
• то = then

In Russian, то is often optional, but it is very common when there is a clear contrast or alternative.

Here it helps structure the sentence as:

• If not by bus, then by metro...

So то makes the contrast between the two transport options clearer and more emphatic.

Доеду is the 1st person singular future of доехать.

доехать means to get to a place by transport / to reach by riding.

So:

• я доеду = I will get there / I will make it there

This verb fits very well because the speaker is talking about successfully reaching work.

A few useful comparisons:

• ехать = to be going / to go by vehicle
• поехать = to set off / to go
• доехать = to get as far as / to reach
• приехать = to arrive

In this sentence, доеду до работы emphasizes managing to get all the way to work.

Because the verb доехать normally goes with до + genitive.

So the standard pattern is:

• доехать до работы
• доехать до дома
• доехать до станции

This means to get to work / home / the station.

By contrast:

• ехать на работу = to go to work
• поехать на работу = to go off to work

So:

• ехать на работу focuses on the direction or destination in a general way
• доехать до работы focuses on successfully reaching that destination

That is why до работы is the correct choice with доеду.

It is genitive singular.

That is because the preposition до requires the genitive case.

So:

• работа → nominative
• до работы → genitive after до

This is a very common pattern:

• до дома
• до школы
• до офиса
• до работы

Всё равно means something like:

• anyway
• all the same
• still
• regardless

In this sentence it shows that the result does not change:

• bus or metro, I will still get to work on time

So the idea is:

• Even if it’s not by bus, I’ll still make it by metro

It adds a sense of persistence or unaffected outcome.

Yes, it could be omitted.

Russian often leaves out subject pronouns when they are clear from the verb ending. So this is also possible:

• Если не автобусом, то на метро всё равно доеду до работы вовремя.

That still clearly means I will get to work on time, because доеду already shows 1st person singular.

Including я gives a little extra emphasis or clarity. It can make the statement feel slightly more explicit:

• I’ll still get there on time

So both versions are natural.

Russian word order is flexible, and this sentence puts the main contrast first:

• Если не автобусом, то на метро

That immediately highlights the two transport options.

Then comes the main claim:

• я всё равно доеду до работы вовремя

So the structure is roughly:

1. contrast of means
2. reassurance about the outcome

This is very natural Russian word order for emphasis.

Other word orders are possible, but they shift focus slightly. For example:

• Я всё равно доеду до работы вовремя, если не автобусом, то на метро.

This version puts the result first and the transport contrast later.

They are different words.

• вовремя = on time
  This is an adverb.
• во время = during
  This is a preposition + noun

So here:

• доеду до работы вовремя = I’ll get to work on time

But:

• во время урока = during the lesson
• во время поездки = during the trip

So in your sentence, it must be the one-word adverb вовремя.

It sounds more like confidence.

The speaker is saying:

• even if one method does not work, another one will
• and the final result will still be the same

The combination of:

• если не ..., то ...
• всё равно
• доеду
• вовремя

makes the sentence sound reassuring and determined:

• If not by bus, then by metro — I’ll still get to work on time.

So the speaker is not just considering possibilities; they are expressing confidence that they can solve the problem.

Here it clearly means not by bus.

That is because автобусом is in the instrumental case, which commonly expresses the means by which something is done.

So:

• не автобусом = not by bus
• на метро = by metro

This is not about choosing the wrong bus or saying it isn’t a bus. It is specifically about the mode of transport.

The whole contrast is between two means of getting somewhere.