The present invention relates to a process and system for complete conversion of crude oils by integrating Desalter unit, Atmospheric and vacuum column, high severity FCC process, Naphtha cracking process, residue slurry hydrocracking process, Delayed coking process, Selective mild hydrocracking aromatic production unit, Dehydrogenation units, Aromatic/olefin recovery section, gasifier unit along with syngas to olefins conversion section.