Can i beat LANCE with my team ?

The best way to beat Lance is to have Pokemon that know strong, yet durable ice moves like ice pokemon with high level. They should also know moves that can prevent other pokemon's moves such as freezing or sleeping moves so that you have time to revive your Pokemon or that you can attack other Pokemon without getting attacked yourself. Rock pokemon or rock moves are also good against Lance's Pokemon but ice Pokemon are the most preferable type. Good Luck!