Redpath represented England under-20 in the 2018 Six Nations Under 20s Championship, scoring tries against Wales and France. Redpath was selected in England's 34-man squad for their 2018 summer tour of South Africa but was unable to travel with the squad because of injury. He scored a try against Scotland in the 2019 Six Nations Under 20s Championship. He also played at the 2019 World Rugby Under 20 Championship however his tournament came to an end when he received a six-week ban for biting an opponent in their penultimate match against Ireland.