Openings in slabs are provided mainly for service works. According to the purpose of the services, the size of the openings was classified as small, medium, and large. The provision of openings in a composite slab was not addressed in design codes like EC-4 and IS 11384. Normally the Longitudinal shear interaction is the influencing factor in determining the capacity and elastic rigidity of a composite slab which may be affected by the presence of openings. In the market, there are various forms of embossment/indentation available to enhance the interlocking at the interface of the Cold Form Steel decking sheet and the topping concrete thereby an increased longitudinal shear resistance can be achieved at the interface. In this numerical study, Among the various type of embossments, combined types of embossments (rectangular and chevron) are considered then the m and k values are determined with the help of the Penalty Friction interaction approach and the same was verified with the known experimental values for a solid slab. In addition, Finite Element [FE] models with various sizes of floor openings were created under the guidelines of SCI publication P300 and SDI Technical Guidance on Deck Damage and Penetrations. The effects of those openings located in the high shear region and no shear region are studied. The simulated load-deflection responses of various FE floor opening models were compared.