The 24-year-old has already won two senior caps for England thanks to his fine form at Burnley last season and the former Manchester United youngster is determined to push on with both club and country.
"I thought Everton was a club that was going in the right direction and one that I can fit into really well," Keane said.
"I feel like it's the right time for me to come to this type of club where I'll be taking another step into the Europa League, which I've never played before.
"I want to try and push on some so I can force myself into the England team. First of all I need to keep myself in the squad, keep fit and playing games here at Everton and playing well - that's my main focus.
"In the back of my mind I've always got England and the World Cup in the summer. I know if I can impress, I'll put myself in the manager's thoughts and hopefully I can do that."