Question

He asked her if she could come write him.(change into a direct question)

Answer 1

Hey there!

Dear I think there is a mistake in your sentence. It actually should be,
He asked her if she could come with him.

So after converting,
He asked her, "Can you come with me?".

Hope it helps.

Answer 2

Hey!

The above sentence in the question is in indirect speech.

Here is your required answer!

He said, " Can you come with me?"

Hope this helps...!!

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