average lifespan of labs is around 10 years above
depends how well you take care of them.
i suggested these breeds because they are low risk in having a confrontation with other people especially children. because they are very patient.
but as what ironwood said you have to study and understand the breed before jumping in. raising a dog takes time effort money and patience. some dogs doesnt do well if left alone and can be destructive. some dogs are aggressive with strangers. some dogs bark a lot.
look for a dog that is right for you. there are tons of information in google you can start there.