Multi input Dc-Dc Converter controlled by arduino uno

Hi There,
I’m Working On Project Of 2 Dc’s Power Supply(S.C And Lithium-ion Battery) goes on Two Mosfet And An Inductor And An Capacitor Last Thing The Load Wich Is 12 Dc Motor.
I Want To Make The Duty Cycle Of The Mosfet Controlled By The Arduino Uno Please Can You Suggest The Type Of The Mosfet and The Two Sources Are 12V and 18V.
My regards.