You could import these field into separate fields and then have a calculation to combined this field into one after import.
actor & " " & character
actor is John Doe
character is Mickey Mouse
results would be John Doe Mickey Mouse
I need to take that information and create new table with one record for each actor character combination.
I don't see how that requires importing data from multiple fields in one table into one field in the other.
A classic way to manage this data is with a many to many relationship. The FileMaker Training Series book actually uses a data base of actors, their roles and the movies they act in for an example of exactly this situation.
Start with these relationships:
Actors::__pkActorID = Roles::_fkActorID
Shows::__pkShowID = Roles::_fkShowID
You can place a portal to Roles on the Actors layout to list and select a Shows record for each given Actors record. Fields from Shows can be included in the Portal to show additional info about each selected Shows record and the _fkShowID field can be set up with a value list for selecting Shows records by their ID field. And a field in Roles can be used to name the character portrayed in that Role.