The phrase "to take on new challenges" means to accept or undertake something that is difficult, unfamiliar or presents a significant obstacle. Full definition
After 25 years practicing law, I am ready to take on a new challenge in a related field. (members.climber.com)
He is an avid traveler and reader, and keen to take on new challenges with patience and perseverance, addressing any problem in a systematic method. (greenplanet.com)
Keeping busy or taking on new challenges at work or at home can help ease the sense of loss that your child's departure might cause. (mayoclinic.org)