How to remove a habit in a kid who learned writing before reading?

My girlfriend started to work recently in a school/kindergarden made for kids who need help with their development (in a non-English speaking small country).
She is new to the field and there aren't many resources for her to use.

She is trying to help a kid, who is a bit behind with reading.
The problem is he was taught to write along with pronouncing letters.
Now, when he reads a text, he uses a ruler/pencil to follow the letters
and he "writes each letter in the air" to recall it and then pronounces syllables.
The kid uses hand motorics to connect written symbols to match them with the sounds.

Have you guys meet anything similar in your practice?
Are there any techniques or exercises to help him to relearn reading
(rewire and stop using hand motorics to vocalize written text. Thank you.