Inspired by the remarkable grasping and locomotion capabilities of octopus arms, this paper presents the design, fabrication, and experimental evaluation of a bio-inspired soft robotic arm capable of object grasping and bipedal locomotion in both aquatic and terrestrial environments. By integrating soft materials, pneumatic actuation, and control systems, the soft robotic arm replicates key biological features and functions of octopus arms, enabling object grasping and bipedal locomotion in amphibious environments. Experimental results show that the soft robotic arm can grasp objects with diameters ranging from 52 mm to 76 mm, supporting a maximum payload of 185 g in air and 524.5 g underwater. In addition, a pair of robotic arms enables effective underwater bipedal locomotion at 1.51 cm/s. These findings validate the effectiveness of the proposed design and highlight its potential for practical applications in amphibious environments.