The 21-year-old debuted for his country at the age of 18 to become its youngest senior player in 2011 and has earned 12 international caps so far.
He spoke to Everton’s official site and said: “I know Everton is a really traditional club and the supporters are fantastic here. I think it is the biggest step for me after leaving Hungary.
"I think my style is suited to playing in the Premier League and I think this is the best league in the world.
“It will be difficult for me because we have fantastic players but I think, with the help of the coach, I will do my best. The World Cup was really important and I think the most important game for me was the Argentina game”, continued the youngster.
“I think I did a good job and many clubs were looking, including Mr Martinez. I can play anywhere but I think I will play as a central midfielder for Everton. I enjoy playing in midfield because I get to see a lot of the ball and I think it is my best position," concluded the latest Everton signing.