I have a field name Sec_field i want to know list of dashboards are using this field <Sec_field> is it possible to get using a SPL
Yes, it is possible. Start with the REST command that provides all dashboard data then filter for those that contain the desired field. Something like this should get you started:
| rest /servicesNS/-/-/data/ui/views splunk_server=local
| search data="*sec_field*"
| table title eai:acl.app author data