To renew a driving license in Bihar, individuals need to visit the nearest Regional Transport Office (RTO) or utilize the online portal. The process involves submitting a renewal application, along with required documents like the expired license, proof of address and age, and passport-sized photographs. For applicants over 40, a medical certificate (Form 1A) is also necessary. Fees are applicable for the renewal process, and the renewed license will be delivered to the registered address upon successful verification.