My cat licks fur, has scabs, had seizure from flea meds. What to do?

Thanks for using Petco Pet Education Center, formerly Petcoach! It does sound like Puppet has fleas and is allergic to their bite. Some over the counter flea medications are not safe for cats. I recommend taking Puppet to a vet for an exam and safe flea preventions. She needs treatment for the flea allergy too as that won’t go away until the fleas are properly addressed. A collar will help stop the licking but the need to scratch won’t stop unless you take care of the fleas with veterinary approved products (not purchased from a store). Good luck and kisses to Puppet!