how do i access values in this field? i am using record.getValue('shipphone') but i get nothing, i see that in netsuite fields explorer i tried getsubrecord but it says 'subrecord doesnt exist for the the field ship address'

Have you tried the field 'shippingaddress' for subrecord ? This ship to select has internal id shipaddresslist, it populates existing addresses from customer records, but you can create new from here as well.