There is no specific action for “saving” a record. When a record is first created, it’s automatically saved. Any time you edit any field in the record, those changes are immediately saved as well. Watch the upper-left corner of the Airtable UI, and notice how it shows you that it’s saving data even before you’ve finished editing a given field.
If you’re always going to use those three fields to create the primary field name, you could turn the primary field into a formula that always concatenates those other fields’ values. However, this will prevent you from manually editing that field. Fields can be automatically driven (formulas, lookups, rollups, etc.) or manually entered (text, number, email, etc.), but not both.
Another possibility is to use an automation to take those three pieces to create the primary field name. However, setting up a trigger might be tricky, because you could easily get incomplete data. Then again, if you’re always adding records to your table using a form, an automation could work well. In the end, the effectiveness of an automation would depend to a great degree on your desired workflow for entering new records.
