Хоть мы и устали, мы всё равно помогли фермеру принести воду в конюшню.

In this sentence, хоть means although / even though, not at least.

So:

• Хоть мы и устали... = Even though we were tired...

This is a very common use of хоть in conversational Russian. A slightly more neutral or formal version is хотя:

• Хотя мы и устали...

Both are correct here. Хоть often sounds a bit more colloquial.

Here, и is not the normal and. It is a particle used in the pattern:

• хоть ... и ...
• хотя ... и ...

This pattern strengthens the idea of concession: although / even though.

So:

• Хоть мы и устали = Even though we were tired
• not literally Though we and got tired

The и is very common in this structure, though Russian can sometimes omit it:

• Хотя мы устали, ...
• Хотя мы и устали, ...

Both are possible, but the version with и is very natural.

Yes, they both contribute to the contrast, and Russian often likes this kind of double marking.

• Хоть мы и устали = Even though we were tired
• мы всё равно помогли = we helped anyway / all the same

Together they make the contrast very clear:

• Even though we were tired, we still helped...

This is completely natural in Russian. English can do something similar:

• Although we were tired, we still helped.

Russian often sounds especially idiomatic with both parts present.

Устали is the past tense plural form of устать, which is a perfective verb.

• устать = to get tired / become tired
• устали = (we/they) got tired / became tired

In English, this often gets translated simply as were tired, because the important idea is the resulting state.

Why not уставали? Because уставали is imperfective and usually suggests a repeated or ongoing process:

• Мы уставали каждый день. = We used to get tired every day.

Here the sentence refers to a single situation, so устали is the natural choice.

Помогли is the past plural of помочь (perfective), and it is used because the sentence describes a completed action:

• we helped

The helping happened on one specific occasion and is viewed as a finished event.

Compare:

• помогли = helped once / completed the helping
• помогали = were helping / used to help / helped repeatedly

In this sentence, the perfective form fits best because the action is a single completed event.

Because the verb помочь / помогать takes the person being helped in the dative.

So the pattern is:

• помочь кому? = to help whom? → dative

Examples:

• помочь другу = help a friend
• помочь маме = help Mom
• помочь фермеру = help the farmer

That is why it is фермеру, not фермера.

Russian often uses this structure:

• помочь кому-то + infinitive
• to help someone do something

So:

• помогли фермеру принести воду = helped the farmer bring water

This is a very common construction.

You can think of it as:

• We helped the farmer
  do what?
  bring water

Because принести is perfective and refers to a completed act of bringing something to a destination.

• принести = bring, carry and successfully deliver
• приносить = bring regularly / be bringing / bring as a process

Here the idea is one completed action: they helped the farmer bring the water into the stable. So принести is the natural choice.

If it were about repeated or habitual action, you might see приносить:

• Мы часто помогали фермеру приносить воду.
• We often helped the farmer bring water.

Because вода is the direct object of принести.

Ask:

• принести что? = bring what?
• answer: воду

For a feminine noun ending in -а, the accusative singular usually changes -а to -у:

• вода → воду

So:

• принести воду = to bring water

Because Russian uses different cases after в depending on whether you mean motion toward/into something or location in something.

Motion into / toward something

• в + accusative
• в конюшню = into the stable / to the stable

Location inside something

• в + prepositional
• в конюшне = in the stable

Since the sentence is about carrying water into the stable, Russian uses the accusative:

• в конюшню

Yes, Russian could leave it out:

• Хоть мы и устали, всё равно помогли фермеру...

That is perfectly natural.

But repeating мы is also natural and can make the sentence a bit clearer or more balanced:

• Хоть мы и устали, мы всё равно помогли...

It slightly emphasizes the subject and makes the contrast feel more explicit: even though we were tired, we still helped.

Yes. The first part, Хоть мы и устали, is a subordinate clause, and it is separated from the main clause by a comma.

So the structure is:

• Хоть мы и устали,
• мы всё равно помогли фермеру принести воду в конюшню.

This is standard Russian punctuation for a sentence with although / even though.