"set out on a mission" is correct and usable in written English. You can use it to refer to beginning a task or a journey with a determined purpose in mind. For example, "With the help of their team of experts, the company set out on a mission to build a new software platform.".
Last year, our Healthy Food in Health Care team set out on a mission: convince hospitals across the country to serve at least one meal featuring sustainably raised meat on Food Day.
She fired her trainer, and immediately set out on a mission to shed the unwanted pounds on her own.
Without telling his brother, Jes set out on a mission to change the homophobic culture of Wall Street.
SOON after we became New Yorkers two years ago, my husband and I set out on a mission.
Nebraska stars 1970s veteran Bruce Dern as Woody Grant, a befuddled alcoholic who sets out on a mission to redeem what he believes is a winning lottery ticket.
He sets out on a mission across Europe in an effort to find out who wants to kill him, a challenge complicated by the fact he is suffering from post-traumatic stress disorder.
In "Isn't It Romantic?" a Bond-like operative identified only as N sets out on a mission in the French Pyrenees entailing good food, fast cars, esoteric trade talk and sexy women.
Thanks to Ludwig my first paper got accepted! The editor wrote me that my manuscript was well-written
Listya Utami K.
PhD Student in Biology, Bandung Institute of Technology, Indonesia