Roy Hodgson’s side's journey in Poland and Ukraine came to a disappointing end on Sunday night after being beaten by Italy on penalties after a goalless 120 minutes.
Despite topping their group ahead of France, England were comfortably second best throughout their last-eight tie with the Azzurri.
However, Walcott, who failed to start for England despite having a positive impact off the substitutes' bench, believes his country can take heart from their adventure and feels the future looks good for the Three Lions.
"I think that, in a short amount of time, the way Roy got the team to play was great to watch at times," he said.
"We are only going to be better players going into the World Cup qualification matches because we will learn more. We will play teams that aren’t as good as those we have played in this competition."
The Arsenal player, who rose to fame in 2006 when he was surprisingly included in Sven-Goran Eriksson’s World Cup squad despite not making a professional appearance for the Gunners, also admitted that the knowledge learnt during the summer will prepare the younger players better for the next tournament.
"There are a lot of young players who have gained good experience, me being one of them," he said.
"Going into the next tournament, we will be better and there are loads more players who can get into this team as well.
"It is most important that we have a rest now because it has been a long season for everyone. I am not going to think about football. I think it is important to rest mentally, not just physically, because it’s always up and down and can be tough."
By Matt Maltby
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