The Manchester City full-back is one of the more experienced players in the squad, having featured for the Three Lions for eight years.
England have failed to live up to expectations in recent tournaments, but Walker is confident that the team have improved.
"It was difficult to take, I'm not going to lie and say there were loads of positives," Walker told The Guardian when asked about England's defeat to Iceland in Euro 2016.
"It was a negative. In the game against Iceland my feeling was that things were going to plan when we went 1-0 up. Instead scoring an early goal might have put us off our guard. I don't believe we thought we were already through but we were beginning to feel seeing out the game might be easy when a long throw came in and caught us by surprise.
"The whole vibe around England now is completely different. It is a younger set of players and we are taking huge steps in the right direction but we still probably need to get more streetwise. English footballers are honest, they will run for 90-odd minutes, but that is not always what you need. Sometimes you need to rein back a bit and try and control the game with your passing. When we come up against Belgium, say, it could be a deciding game but we need to realise that we don't have to score in the first 10 minutes.
"If you can control the game you can wait until the 80th minute or longer if necessary. I'm trying to bring that calmness from Manchester City, and so is John [Stones]. I've adapted my own game a bit since changing club. I stay back a bit more. When I was at Tottenham the fans wanted attack, attack, attack but, if you send too many bodies forward, you are liable for the counter. With England we are working in training on controlling situations a little better. If we can make it work on the pitch we will hopefully have a good tournament."
England will play Belgium, Panama and Tunisia in the group stages of the World Cup next month.