Page title from the exposed filter term
To use term names in a Contextual filter in Content views you need to add the Relationship to the taxonomy reference field you have in your content. Then you'll be able to add Taxonomy term: Name Contextual filter that will take names as arguments, and not term ID numbers. 

You will be able to override the title for the Name contextual the same way, only use the corresponding token for the taxonomy name. You can look it up under Replacement patterns. 

You can find more details about how to set up the Name contextual here in a section of this answer: Create view with path relative to taxonomy term