Monday's match features the two strongest teams in Group G, which also includes Iran and New Zealand, meaning the game is not necessarily a must-win for either side.
A last-32 – and potentially last-16 – game in Seattle near to both teams' base camps awaits the winner of the group, however, and the contest presents a great opportunity for Belgium or Egypt to take the initiative, Garcia said.
"We are going to focus on our strengths, we want to be protagonists," Garcia told reporters, adding: "We really need to go all-in tomorrow as if it is the final."
He was highly complimentary towards an Egypt side featuring world-class talent in forwards Mohamed Salah and Omar Marmoush, and also boasting a strong defensive record, saying: "It is one of the best African squads of all time."
But he added: "All teams have weaknesses... we will see tomorrow if we can exploit those weaknesses."
Garcia happy to have hydration breaks
Belgium crashed out in the group stage in 2022 and Garcia was circumspect when asked what he was aiming for with a talented squad at his disposal.
"It's step by step – get out of the group stage, but we want to finish top of the pool," he said.
To do so, they will first have to deal with high temperatures in Seattle, which will be helped by hydration breaks – though Garcia said they were significant in other ways.
"For me, it's a coaching break more than a cooling break, so to me it's very important," Garcia said.
Monday will mark Garcia's first game managing at a World Cup, as well as captain Youri Tielemans' first time leading Belgium at a major tournament.
The midfielder said he hoped to take the positivity from Aston Villa's Europa League triumph last month, but like his coach, sounded a note of caution.
"I can tell every first game's very nervous... so it's going to be up to us to start well," Tielemans said. He added: "Go for it, no regrets and then anything can happen."
Follow the game with Flashscore.
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
Match schedule and times | Group tables | Full squads for World Cup | How to watch the World Cup