Are herbal products the same as wormers?

No.  Wormers are licensed veterinary medicines, which are proven to treat worms e.g. Flubenvet.  You should always speak to a Vet or (SQP) suitably qualified person before treating your chickens. Herbal products such as Nettex Herbal Gut Conditioner can be used alongside a licensed wormer to help restore a healthy gut flora following treatment for worms.