Charlton died last month and will be honoured by the Football Association at Wembley on Friday night when England face Malta.
There will be a crowd mosaic and big-screen video celebrating his life, followed by a pre-match ceremony and a period of applause. Players will also wear black armbands.
Southgate has showed his players clips of Charlton, who helped England win their only World Cup in 1966, during their time in camp this week.
The England manager has always wanted to stress the importance of the side’s history to his squad, while also underline the legacy they can leave by winning a trophy.
“A big part of what we have wanted to do with our players is to talk about our identity as a team,” said Southgate.
“Part of that is knowing the history of our team and having an understanding of how special some of the players that have been England internationals before are.
“We have had the chance to do that this week. We showed some footage of Sir Bobby to the players the first day we arrived.
“You can have a fabulous club career and an international career. At times those things can come into conflict because club managers of course have got to look after their own roles and responsibility. That can put players in difficult positions with all internationals, frankly.
“But your international team will always be there as well and if you can win something with your international team, it is probably bigger than anything else you are going to experience.
“There are lots of messages within that for all of the players, but most importantly an incredible player, an incredible man. I thought the occasion (Charlton's funeral) on Monday was brilliantly handled by everyone at the cathedral and Manchester United.
“We wanted to go because we wanted England to be represented. We hope we have been a big part of his life and his family’s life. We felt it was important to be there.”
England have already qualified for Euro 2024 next summer, but they still want to win their final two games against Malta and North Macedonia to ensure they are top seeds for the tournament in Germany.
They have been hit by injuries ahead of this camp, though, with five players named in Southgate’s original squad pulling out.Unlike at the last two tournaments, countries will only be allowed to name 23 and not 26 players in their final squads for the Euros - and Southgate has stressed how he cannot take those who aren’t fully fit.
“It’s tough for players, like Ben [Chilwell], like Reece James, who have missed a lot of football. They both missed the World Cup,” he said.
“So for both of them it is not a situation where it is an overload of what they have had football wise.
“Of course for us you need players now, if we can only take 23 players next summer, then that physical robustness is a consideration, because we won’t have the option to take as many chances as we took in the last couple of tournaments.
“The last Euros we took Kalvin Phillips, who had popped his shoulder and had a bit of time to come back in. Harry Maguire for the Euros missed the first couple of games, he was still recovering. Kyle Walker in Qatar [was in the same situation].
“That’s a bigger gamble next time around that we would have to consider on each individual case, but those parameters do alter your thinking a bit on the squad.”