Sheffield Steelers' duo Liam Kirk and Kieran Brown played key roles in GB's 6-3 win over hosts Estonia in Division II Group A, with a four-goal first period proving the key spell in the game.
The hosts briefly threatened a comeback in the second after going 5-0 down by making it a two-goal game, but GB's youngsters steadied themselves to close out a goalless third period and run out comfortable winners.
"It was a great team performance and one everyone can be proud of," said head coach Hand. "We got a little excited going 5-0 up and had to calm ourselves down again, but we were composed and disciplined in those first 20 minutes.
"It was an excellent start to the tournament and one we can certainly build on."
The deadlock was quickly broken when Cade Neilson's shot off the back boards fell kindly to Mason Alderson who poked the puck home (1:55) before - just 10 seconds later - the Guildford Firekings forward grabbed his second from close range..
Richard Krogh's neat backhand finish made it 3-0 at 11:45 before Steelers' Brown fed Jordan Buesa to skate in on the Estonia netminder and score short-handed through the five-hole at 19:16.
Just 90 seconds had elapsed in the second before Buesa's second made it 5-0. It seemed game over.
But GB came under intense pressure, Jegor Nevzorov scoring from a goalmouth scramble (24:31) to signal the hosts' fightback, with Nikita Puzakov stepping out from behind the net to jam home short-handed at 31:52.
Rasmus Kiik then floated in Estonia's third on the powerplay at 37:10, but GB restored their three-goal cushion only 21 seconds later as Patrick Larkin put away a rebound at 37:31.
GB return to action on Monday when they take Australia (2:30pm UK time).
GB Women maintain winning run in Slovenia
GB Women made it two wins from two at the World Championship Division II Group A with a 3-1 victory over DPR Korea in Maribor, Slovenia.
Angela Taylor and Leanne Ganney both scored their third goals of the tournament, with Georgina Farman also getting on the scoresheet, while netminder Nicole Jackson made 13 saves.
Assistant coach, James Ashton, said: "This was another good performance - we lost to this team last year so is another fantastic result for us and the momentum keeps moving."