אני לא רוצה לקנות סוכרייה לפני השיעור.

A common pronunciation is:

ani lo rotse/rotsa liknot sukariya lifnei ha-shiur

A more detailed breakdown:

• אני — a-NI
• לא — lo
• רוצה — ro-TSE if the speaker is male, ro-TSA if the speaker is female
• לקנות — lik-NOT
• סוכרייה — su-ka-ri-YA
• לפני — lif-NEI
• השיעור — ha-shi-UR

Hebrew stress often falls near the end of the word, as in likNOT, lifNEI, shiUR.

לא is the normal Hebrew word for not.

In this sentence, it negates the verb phrase:

• אני רוצה — I want
• אני לא רוצה — I do not want / I don’t want

Unlike English, Hebrew does not need a separate helping verb like do. So Hebrew says literally:

• I not want to buy...

That is the normal way to say I don’t want to buy...

After verbs like want, Hebrew usually uses the infinitive for the second verb.

So:

• רוצה — want
• לקנות — to buy

Together:

• רוצה לקנות — want to buy

This works much like English want to buy, need to go, like to read, etc.

The ל־ is the normal marker that often appears on Hebrew infinitives. In many cases, it corresponds to English to.

So:

• לקנות — to buy
• ללכת — to go
• לראות — to see

In this sentence, לקנות means to buy.

It is not a separate word here; it is attached directly to the verb.

Hebrew does not have an indefinite article like English a or an.

So:

• סוכרייה can mean a candy
• depending on context, it can also be understood more generally as candy

If you want to say the candy, Hebrew adds ה־:

• הסוכרייה — the candy

So the absence of ה־ usually makes the noun indefinite.

Yes, סוכרייה is a feminine singular noun.

In this sentence, that does not change any surrounding words, because there is no adjective or verb agreeing with it. But it can matter in other sentences.

For example:

• סוכרייה טעימה — a tasty candy
  The adjective טעימה is feminine singular to match סוכרייה.

A useful detail:

• singular: סוכרייה
• plural: סוכריות

The ה־ is the definite article, meaning the.

So:

• שיעור — lesson / class
• השיעור — the lesson / the class

In לפני השיעור, the speaker means a specific lesson/class, probably one already understood from context.

So:

• לפני השיעור — before the lesson / before class

If you removed ה־, it would sound less specific:

• לפני שיעור — before a lesson / before class in a more general sense

Here, לפני means before in a time sense.

So:

• לפני השיעור — before the lesson / before class

Hebrew לפני can also mean in front of in some contexts, but here the context is clearly temporal, not physical.

Examples:

• לפני השיעור — before the class
• לפני הבית — in front of the house

So the meaning depends on context.

The sentence uses a very normal word order:

• אני — subject
• לא רוצה — negated verb
• לקנות — infinitive
• סוכרייה — object
• לפני השיעור — time phrase

So the structure is:

• I + not want + to buy + candy + before the lesson

This order is natural and common.

Hebrew word order is somewhat flexible, though. For emphasis, you could move the time phrase:

• לפני השיעור אני לא רוצה לקנות סוכרייה

That still means the same thing, but now before the lesson is highlighted.

From the spelling without vowel marks, you actually cannot be completely sure just from רוצה.

That is because:

• masculine: רוֹצֶה
• feminine: רוֹצָה

But in normal unpointed writing, both are usually written רוצה.

So this sentence could mean either:

• I (male) don’t want to buy a candy before the lesson
• I (female) don’t want to buy a candy before the lesson

You usually know from:

• context
• who is speaking
• or actual pronunciation

In speech:

• male speaker: rotse
• female speaker: rotsa