Learn Hardcore Norwegian: Hun ber broren sin om hjelp til å logge inn på den nye kontoen. - She asks her brother for help to log in to the new account.

broren sin = her own brother (reflexive possessive)
broren hennes = another woman’s / some other female person’s brother (not the subject’s)

In the sentence Hun ber broren sin om hjelp..., the subject is hun, so sin refers back to that same subject: She asks *her own brother for help.*

If you said Hun ber broren hennes om hjelp, it would mean: She asks *some other woman’s brother for help.*

Can I just say Hun ber broren om hjelp and leave out sin?

You can, and it is grammatically correct, but it becomes less clear whose brother it is.

Hun ber broren sin om hjelp → strongly suggests it is her own brother.
Hun ber broren om hjelp → could be her brother, or just the brother (known from context); it is more neutral/ambiguous.

In practice, Norwegians often keep sin when they want to make the “her own” relationship explicit.

What is the difference between ber and spør? Why not Hun spør broren sin om hjelp?

å be (noen) om (noe) = to ask (someone) for (something), to request
- Hun ber broren sin om hjelp. = She asks her brother for help.
å spørre (noen) om (noe) = to ask (someone) (a question), to inquire
- Hun spør broren sin om passordet. = She asks her brother about the password.

So:

If you are asking for something (help, money, a favor), use be om.
If you are asking a question / about information, use spørre.

That is why ber ... om hjelp is the natural choice here.

What does om do in ber broren sin om hjelp? Could we leave it out?

In this construction, om belongs to the verb å be:

Pattern: be (noen) om (noe) = ask (someone) for (something)

om introduces what you are asking for:

Han ber henne om penger. = He asks her for money.
Vi ber læreren om ekstra tid. = We ask the teacher for extra time.

You cannot leave out om here.
✗ Hun ber broren sin hjelp is incorrect. It must be Hun ber broren sin om hjelp.

Why do we say om hjelp til å logge inn? What is the role of til?

Here the structure is:

om hjelp til å logge inn
- om hjelp = for help
- til å logge inn = to log in (for the purpose of logging in)

Two things are going on:

The noun hjelp often takes til when followed by an infinitive:
- hjelp til å forstå = help to understand
- hjelp til å flytte = help to move
The å is the infinitive marker before logge.

So til connects the noun hjelp with the verb phrase å logge inn.
You normally do not drop til in this pattern: hjelp til å ... is standard.

Why is it å logge inn and not just å logge? What does inn do?

logge inn is a particle verb:

logge = to log (in general; not commonly used alone in everyday speech)
logge inn = to log in / sign in
logge ut = to log out
logge på (alternative) = to log on

The particle inn changes the meaning to the specific IT action log in.
So å logge inn directly corresponds to English to log in.

Why is it logge inn på den nye kontoen and not i den nye kontoen or til den nye kontoen?

For IT contexts, the usual preposition is på:

logge inn på kontoen = log in to the account
logge inn på e‑posten = log in to the email
logge inn på systemet = log in to the system

In English you use in / into, but Norwegian often uses på with services, accounts, websites, etc.
i kontoen would sound more like physically inside something, which doesn’t fit the digital context here.

Why do we say den nye kontoen and not den ny konto?

Norwegian has double definiteness with most nouns:

article (den / det / de)
- adjective in definite form (nye)
- noun in definite form (kontoen)

So:

en ny konto = a new account
den nye kontoen = the new account

den ny konto is incorrect in standard Norwegian. You need both the article and the definite ending on the noun when an adjective comes before a definite noun.

Is konto masculine or feminine? Why is it kontoen and not kontoa?

konto is a masculine noun in standard Bokmål:

indefinite singular: en konto
definite singular: kontoen

Many feminine nouns can optionally be treated as feminine (ei bok – boka), but konto is normally treated as masculine. ✗ kontoa is not used in standard Bokmål.

Why is it Hun ber ... and not Henne ber ...?

Hun is the subject form (nominative):

Hun leser. = She is reading.
Hun ber broren sin om hjelp. = She asks her brother for help.

Henne is the object form (accusative):

Jeg ser henne. = I see her.
Han ber henne om hjelp. = He asks her for help.

Subjects must use hun, not henne. So Henne ber ... is incorrect.

Where would ikke go if I say She does not ask her brother for help in Norwegian?

Negation ikke normally comes after the finite verb:

Hun ber ikke broren sin om hjelp til å logge inn på den nye kontoen.
= She does not ask her brother for help to log in to the new account.

Word order pattern:

Subject: Hun
Finite verb: ber
Negation: ikke
Rest of the clause: broren sin om hjelp til å logge inn på den nye kontoen

Is å be irregular? How are its main forms?

Yes, å be (to ask, to pray) is irregular:

infinitive: å be
present: ber
preterite (past): ba or bad (both used; ba is more common in modern usage)
past participle: bedt

Examples:

Hun ber broren sin om hjelp. = She asks her brother for help.
Hun ba / bad broren sin om hjelp. = She asked her brother for help.
Hun har bedt broren sin om hjelp. = She has asked her brother for help.

Can I say hjelp med å logge inn instead of hjelp til å logge inn?

Yes, hjelp med å ... is also used and understandable:

Hun ber broren sin om hjelp til å logge inn.
Hun ber broren sin om hjelp med å logge inn.

Both are acceptable, but:

hjelp til å ... is a very common, neutral pattern.
hjelp med å ... can sound a bit more colloquial or emphasize help with the activity itself.

In your sentence, til å logge inn is probably the most idiomatic choice.