This paper investigates near-field spot beamfocusing (SBF) using holographic antennas for multiuser communication applications. While far-field holographic surfaces have been widely explored, a comprehensive study of nearfield holographic surfaces, especially for precise beam-focusing, remains limited. In this work, we derive a closed-form analytical solution for the focal gap, enabling precise beam-focusing at the intended focal point. We characterize key physical parameters of near-field holographic antennas, including the depth of focus (DoF), angular beamwidth, and the effects of surface impedance quantization. Additionally, we introduce an interference cancellation algorithm that leverages orthogonal beam patterns on the focal plane, enhancing secure communication in multiuser scenarios. Extensive EM simulations and experimental measurements validate the proposed methods, demonstrating effective beam-focusing and interference mitigation for singleand multiuser applications. The results suggest that holographic SBF could be a pivotal technology for next-generation 6G wireless networks, offering significant potential for applications in secure communication, wireless power transfer, and medical technologies.