Complex sentence: Alice Braga will appear as Cecilia Reyes in the 2018 "The New Mutants" film as a mentor to the group, and "a medical doctor who has the ability to generate a protective bio-field around herself".
Split into simpler sentences: Alice Braga will appear as Cecilia Reyes in the 2018 "The New Mutants" film. She appears as a mentor to the group, and "a medical doctor who has the ability to generate a protective bio-field around herself".