The Frenchman was appointed this week to succeed Spaniard Javier Clemente, fired on Monday after Cameroon failed to qualify for the upcoming African Nations Cup finals.
"I know it's not going to be an easy task for me and my assistants. All I can say for now is that we'll do everything to select the best Cameroon players, both at home and abroad, and introduce fresh, young talent into the squad to replace older players," he said on Saturday.
"In order for us to succeed in this very challenging task we'll need the support and co-operation of all Cameroonians."
Lavagne stressed a leading role for African Footballer of the Year Samuel Eto'o, who has been accused by pundits of wielding too much influence in the squad, both over his team mates and former coach Clemente.
The new interim boss, whose only previous management experience was working with Cameroon champions Coton Sport, said Cameroon had lacked offensive midfielders and strong wingers in recent games who could supply Eto'o with opportunities to score.
"Football is a collective sport and one player cannot do everything alone. In order for Eto'o, with his rich experience, to score the goals he needs people around him who will make good passes and provide him the ball at the right time."
Cameroon were eliminated by Senegal in the qualifiers for the 2012 Africa Cup of Nations finals, only their second failure in their last 16 attempts to reach the tournament.
On top of the World Cup mission, Lavagne will also have the immediate task of qualifying Cameroon for the 2013 Africa Cup of Nations finals in South Africa.
Cameroon begin their World Cup preliminaries next June.
Lavagne on Friday recalled Tottenham Hotspur full back Benoit Assou Ekotto, midfielder Jean Makoun and striker Somen Tchoyi to a 28-man squad for three friendlies in November.
Cameroon play Sudan on November 11 and Morocco on November 13 in Marrakech before travelling to Algeria for a third friendly on November 15.
