First, pull out the actual text value of the phone number.
Do this by saying: phoneNumberColumn.phoneNumber
Essentially chain it out.
Then, It looks like the number is in the format you need already, except for the spaces right?
If so, you can say: regexReplace(“\s”, “”)
If it’s any more complex that you can use the phone numbers pack which will format numbers into a variety or proper phone number formats.