How to find a field name/column name of a field in database where I have only the label of that field? I am working on an integration part with drupal framework. Here it's hard to  find the table names of the field which is present in the view as I know only the field label name. 

Is there any way to sort this out?
You can derive the database table name by the host entity and the field name. The name schema is ENTITYTYPE__FIELDNAME

Views don't directly show the field name, but you can look at the entity's "Manage field" page to get the field name by label. (e.g. for nodes /admin/structure/types/manage/BUNDLENAME/fields)

Examples:

node__body
node__field_image
users__field_whatsapp
taxonomy_term__field_text


Exception:
Some special fields (like title or created) are stored as a column on the base table of an entity. Base tables follow the schema ENTITYTYPE_field_data, e.g.

node_field_data
users_field_data
taxonomy_term_field_data