A general methodology for obtaining the reflection and transmission dyads from a general bianisotropic metasurface under oblique incidence have been developed. In this case, it is assumed that the normal electric and magnetic surface polarization currents are negligible. The proposed theory is then used for a metasurface composed of chiral spheres under normal illumination. It is shown that due to an additional parameter of chirality, one can control the reflection, transmission and absorption properties of a metasurface. It is also studied that a metasurface composed of chiral spheres may be used as almost perfect reflector, perfect anti-reflector and good absorber having some specific geometrical and electromagnetic parameters. For completeness, the analytic expressions for electric, magnetic, electromagnetic and magnetoelectric polarizibilities of a chiral sphere have also been derived using Mie theory.