Hamster training - Do not disturb your your hamster when s/he is eating, washing itself, sleeping, etc. Not only will it get annoyed and possibly bite, but it can destroy the trust it may already have for you.
Try hiding berries or small pieces of fruit around your hamster’s cage and watch your hamster find them. Make sure the food is safe for your hamster. Remove fruits and vegetables that haven’t been eaten in 24 hours.