After attaining 3 As at A-Level,[5] he then moved to the University of Leeds to study Biology and was loaned to National League 2 North side Otley R.U.F.C.

[9] In the summer of 2017 De Glanville was a member of the England under-18 team that toured South Africa and the following year he scored two tries against Wales under-18 at Sardis Road.

[12] Later that year he was a member of the squad that finished fifth at the 2019 World Rugby Under 20 Championship and scored a try during the pool stage against Australia.

[7][13] In October 2020 he was called up to a senior England training squad by head coach Eddie Jones.

[17] De Glanville was one of 13 players who breached COVID-19 virus safety protocols by leaving their hotel without permission before a Barbarians game in 2020.