En halua odottaa pitkään pysäkillä.

Finnish negation uses a special negative verb that changes for person.

• en = I do not
• et = you do not
• ei = he/she/it does not
• emme = we do not
• ette = you all do not
• eivät = they do not

So here en is used because the subject is I.

Because in a negative present-tense sentence, the negative verb carries the person information, and the main finite verb loses its personal ending.

So:

• haluan = I want
• en halua = I do not want

This form halua is called the connegative form.

Because haluta normally takes another verb in the first infinitive:

• haluan odottaa = I want to wait
• en halua odottaa = I do not want to wait

Finnish does not need a separate word matching English to in this pattern. The infinitive itself does that job.

Finnish often leaves out subject pronouns when the verb form already makes the subject clear.

Here en already tells you the subject is I, so minä is unnecessary.

You can still say:

• Minä en halua odottaa pitkään pysäkillä.

That sounds more emphatic, contrastive, or explicit.

pitkään is an adverb meaning for a long time or for long.

It comes from pitkä = long, but here it is not an adjective describing a noun. Instead, it describes the action odottaa.

So:

• pitkä = long
• pitkään = for a long time

You can think of odottaa pitkään as a fixed, common pattern meaning to wait a long time.

pysäkillä is the adessive case, which often means at or on a place.

So:

• pysäkillä = at the stop
• pysäkille = to the stop
• pysäkiltä = from the stop

With bus stops, tram stops, and similar places, Finnish commonly uses -lla / -llä for being at the place.

The basic form is pysäkki.

When Finnish adds case endings, the word changes form:

• pysäkki = stop
• pysäkillä = at the stop

So if you want to look it up in a dictionary, search for pysäkki.

Finnish has no articles.

That means there is no direct equivalent of English a/an or the. Context tells you which one makes sense.

So pysäkillä could correspond to:

• at the stop
• at a stop

depending on the situation.

No, Finnish word order is fairly flexible, but the given order is a very natural, neutral one.

• En halua odottaa pitkään pysäkillä.

Because minä is omitted, the sentence starts with en.

You can change the order for emphasis, for example:

• Pysäkillä en halua odottaa pitkään.
• Pitkään en halua odottaa pysäkillä.

These are possible, but they shift emphasis. The original sentence is the most neutral.

Yes. In Finnish, double vowels and double consonants are very important.

In this sentence:

• odottaa has long tt and long aa
• pysäkillä has long ll
• pitkään has long ää

Length can change meaning in Finnish, so it is important to pronounce double letters longer than single ones.