Is it possible to edit formula field values in a Salesforce Record?

No, you can’t edit the formula field on the Page layout. Formula fields are read-only fields in Salesforce.

You need to either set the value via workflow instead – and then edit it after save, or you can look at using Quick Actions to default a value on creation based on a formula. This formula will appear on the Edit (creation) screen and they can then leave it as is or adjust it prior to saving the record.