La lluvia nos hizo cancelar el paseo, así que aproveché para presentar mi esquema a mi hermana.

This is a very common Spanish causative structure:

hacer + infinitive = to make / cause someone to do something

So:

La lluvia nos hizo cancelar el paseo
means
The rain made us cancel the outing

Spanish often uses this structure where English uses make, cause, or force.

Yes. That is also correct and natural.

There are two common ways to express this idea:

• La lluvia nos hizo cancelar el paseo
• La lluvia hizo que canceláramos el paseo

The first one is more compact and direct.
The second uses hacer que + subjunctive and focuses a bit more on the resulting action.

Both are good Spanish.

Because object pronouns like me, te, nos, lo, la, le normally go before a conjugated verb.

So you get:

• nos hizo cancelar
• not hizo nos cancelar

In this sentence, nos means us.

A good learner rule is: with hacer + infinitive, put the pronoun before hacer unless you know there is a special reason not to.

Because both actions are presented as completed events:

• The rain caused the cancellation.
• Then the speaker took the opportunity to do something else.

The Spanish preterite is used for finished actions in a sequence:

• hizo
• aproveché

If you used the imperfect, it would suggest something habitual, ongoing, or backgrounded instead.

Aprovechar para + infinitive means:

• to take the opportunity to...
• to make use of the situation to...

So:

aproveché para presentar mi esquema
means
I took the opportunity to present my outline / plan

This is a very natural Spanish expression.

Así que means so, therefore, or as a result.

It connects the two parts of the sentence:

• the rain made us cancel the outing,
• so I used the time for something else.

It is a very common connector in everyday Spanish.

It is a bit more result-focused than entonces, which often just means then.

Usually no. Esquema is often a false friend for English speakers.

In Spanish, esquema commonly means:

• outline
• plan
• diagram
• framework
• structured summary

So here, mi esquema is probably something like an outline or plan, not a suspicious or secret scheme in the English sense.

Because mi hermana is the recipient of the action.

With presentar, Spanish often follows this pattern:

presentar algo a alguien
= to present something to someone

So in:

presentar mi esquema a mi hermana

• mi esquema = the thing being presented
• a mi hermana = the person receiving it

That a is the normal preposition used with the indirect object.

It could be there.

Spanish often uses an indirect-object pronoun even when the person is named:

• aproveché para presentarle mi esquema a mi hermana
• le presenté mi esquema a mi hermana

That is very common, especially in speech.

But the original version without le is also correct:

• presentar mi esquema a mi hermana

So both patterns are possible.

Because Spanish usually leaves out subject pronouns when the verb ending already shows who the subject is.

aproveché already tells you the subject is yo.

So:

• aproveché = I took the opportunity

You could add yo for emphasis or contrast, but normally it is omitted.

Paseo is broader than just walk.

Depending on context, it can mean:

• a walk
• a stroll
• an outing
• a casual trip out

In this sentence, cancelar el paseo suggests cancelling a planned walk or outing because of the rain.

Spanish often uses the definite article with nouns like this, especially when talking about something identifiable in the situation.

So:

La lluvia nos hizo cancelar el paseo

sounds natural and complete.

Here la lluvia means the rain that was happening and caused the problem.
Using just lluvia would sound unnatural in this sentence.

Because in the first-person singular preterite of regular -ar verbs, the stress falls on the last syllable:

• hablé
• cancelé
• aproveché

The accent mark shows that stress clearly.

Without the accent, aproveche would be read differently and could be interpreted as a subjunctive form or a command-like form instead.