The beauty of cold atom based quantum technologies is that, one can design versatile quantum systems and fully control their properties by simple and clever approaches, just because of the inherent quantum nature of atoms and photons. In one approach we cool atoms to million times colder than room temperature using precisely frequency tuned lasers. In a second approach we trap these cold atoms in optical potentials even to the single particle level. With these abilities, we can design textbook like quantum systems with few individually addressable atoms. The real world problems demand to build large quantum systems beyond textbook examples. The biggest challenge in achieving this goal is to know how to control the environment induced decoherence. In our research group we aim to address these open problems in a step by step manner. These technological and conceptual developments will lead us to build large scale quantum information processing network, quantum computation protocols for solving industry and society relevant problems, quantum sensing devices and quantum metrology modules for precision instrumentations and measurements.