Jeg skrev navnet feil.

Because skrev is the past tense of å skrive.

• å skrive = to write
• skriver = write / am writing
• skrev = wrote
• har skrevet = have written

So Jeg skrev navnet feil is talking about a completed action in the past: I wrote the name wrong.

Navnet is the definite singular form of et navn.

• et navn = a name
• navnet = the name

Norwegian usually adds definiteness to the end of the noun instead of using a separate word like the in English. So navnet already means the name.

In Norwegian, the definite article is often attached to the noun as an ending.

So:

• et navn = a name
• navnet = the name

That means navnet already includes the idea of the, so you do not add another word before it in a simple sentence like this.

Here, feil means wrong or incorrectly.

In this sentence, it works adverbially, meaning it describes how the writing was done. So the idea is:

• Jeg skrev navnet feil = I wrote the name incorrectly

This is a very common Norwegian pattern:

• gjøre noe feil = do something wrong
• si noe feil = say something wrong
• skrive noe feil = write something wrong

Because feil describes the action skrev navnet rather than the noun navnet by itself.

So the structure is basically:

• Jeg = I
• skrev navnet = wrote the name
• feil = wrongly / incorrectly

Putting feil at the end makes it clear that the action of writing was wrong.

They mean different things.

• Jeg skrev navnet feil = I wrote the name incorrectly
  
  • for example, I misspelled it
• Jeg skrev feil navn = I wrote the wrong name
  
  • for example, I wrote Anna when I should have written Anne

So:

• navnet feil = the name was written wrongly
• feil navn = the wrong name

This is an important difference.

They are very close, but not always exactly the same.

• Jeg stavet navnet feil = I spelled the name wrong
• Jeg skrev navnet feil = I wrote the name wrong / incorrectly

Stavet is more specific: it focuses on spelling.

Skrev is a little broader. In many situations, people will understand it as a spelling mistake, but it could also just mean that the name was written incorrectly in some general way.

Yes. That is also correct, but the tense is different.

• Jeg skrev navnet feil = I wrote the name wrong
  
  • simple past, a finished past event
• Jeg har skrevet navnet feil = I have written the name wrong
  
  • present perfect, often used when the mistake is still relevant now

So if you notice the mistake now and want to mention it, Jeg har skrevet navnet feil may feel especially natural.

Yes, it is completely natural in Bokmål.

A native speaker would easily understand it. It is a normal way to say that you wrote a name incorrectly.

If you want to be more specific about spelling, you might also hear:

• Jeg stavet navnet feil

But the original sentence is still natural and correct.