What is axial seal and radial seal, and how to design O-ring groove?

The axial direction is usually for cylindrical objects, that is, the direction of the central axis of rotation of the cylinder, that is, the direction common to the central axis. "Radial" is perpendicular to "axial", that is, the radius or diameter of the end face of the cylinder. The axial seal prevents pressure (fluid) leakage in the axial direction; the radial seal prevents pressure (fluid) leakage in the radial direction. O ring