Hänen takissaan on iso huppu, joten hän ei palele helposti.

Finnish often uses an existential/location structure:

• X:ssa on Y = There is Y in/on X

So:

• Hänen takissaan on iso huppu
• literally: In his/her coat there is a big hood
• natural English: His/her coat has a big hood

This is very normal Finnish. English often uses have, but Finnish often expresses the same idea with there is plus a location.

Takissaan breaks down like this:

• takki = coat
• takissa = in the coat
• takissaan = in his/her coat

So the parts are:

• takki → noun stem
• -ssa → in (the inessive case)
• possessive ending → his/her

So takissaan means in his/her coat.

Yes, they both mark possession.

• hänen = his/her
• the possessive ending in takissaan also shows his/her

In standard Finnish, this kind of double marking is very common and normal, especially in the third person.

So:

• hänen takissaan = in his/her coat

The pronoun hänen helps make the owner explicit, and the possessive ending is part of the normal grammatical structure.

Yes.

Finnish does not mark gender in these pronouns:

• hän = he / she
• hänen = his / her

So from the Finnish sentence alone, you cannot tell whether the person is male or female. The context tells you.

Because the sentence is presenting something as existing in the coat.

Finnish often puts the place/location first in this kind of sentence:

• Hänen takissaan on iso huppu = There is a big hood in his/her coat

If you say:

• Iso huppu on hänen takissaan

that is also grammatical, but the focus changes. It sounds more like you are talking about the big hood and saying where it is.

So:

• takissaan on iso huppu → introduces a feature of the coat
• iso huppu on hänen takissaan → focuses more on the hood itself

Joten means:

• so
• therefore
• which is why

It introduces a result or consequence.

So here:

• Hänen takissaan on iso huppu, joten hän ei palele helposti.
• There is a big hood in his/her coat, so he/she does not get cold easily.

It links the two ideas as cause/result.

Because the second clause needs its own subject:

• joten hän ei palele helposti

In standard Finnish, third-person subjects like hän are usually stated clearly. Repeating hän makes it clear that the same person is the subject of the second clause too.

So the repetition is normal and natural.

Because Finnish negative sentences use:

• a negative verb: ei
• plus a special verb form, not the infinitive

The dictionary form is:

• palella = to feel cold / to be cold

But in the negative present:

• hän palelee = he/she feels cold
• hän ei palele = he/she does not feel cold

So palella is the infinitive, but after ei you need palele.

Palella means:

• to feel cold
• to suffer from the cold
• to get cold

It does not mean to freeze solid.

So:

• hän ei palele helposti = he/she doesn’t get cold easily
• or he/she is not easily bothered by the cold

It refers to the physical sensation of being cold.

Helposti literally means easily.

In this sentence:

• ei palele helposti

it means:

• doesn’t get cold easily
• is not easily made cold
• is not prone to feeling cold

So helposti does not mean the person is doing something easily on purpose. It describes how readily the cold affects them.

Yes, but the tone changes a little.

• iso = big, common and everyday
• suuri = big/large, a bit more formal or neutral depending on context

So:

• iso huppu sounds very natural in everyday Finnish
• suuri huppu is also possible, but often sounds slightly less casual

In this sentence, iso huppu is the most natural everyday choice.