On March 1, 2018, as the first Polish biathlete, she won the title of Junior World Champion in 12,5 km individual competition with a winning time more than 3 minutes ahead of the 2nd place Biathlete. Two days later, she claimed another gold medal, this time in 7.5 km sprint ahead of Czech Markéta Davidová and French Myrtille Bègue. On March 4, 2018 Żuk added silver medal to her achievements from 2018 Junior World Championships in 10 km pursuit, losing only to Czech Davidová at a loss 28.1 sec.