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The existence of massive prestellar cores (PSCs) is crucial in turbulent core accretion model. To find the hints of massive prestellar cores, we first performed high resolution simulations of giant molecular cloud (GMC) collisions. We utilise CASA post-processing the surface density maps to generate their ALMA 1.3mm synthetic observation results. We then use dendrogram to identify cores from the simulations and their corresponding synthetic observations. In chemistry aspect, observations have shown that high levels of deuterium fractionation ([N2D+]/[N2H+]>0.1) are often observed in prestellar cores. Therefore, we also carried out chemodynamics simulations of isolated massive prestellar cores. We studied the chemical evolution of species, especially N2H+ and N2D+, in a variety of initial chemical conditions. Our simulation results are compared with observational data, including the core mass functions (CMFs) of clusters, and the N2H+/N2D+ emissions from prestellar cores. We concluded that (1) the clusters do not have strong evidence of collision from the core mass functions, and (2) high depletion factor and high cosmic ray ionisation rate are required for these cores to achieve high level of deuterium fractionation. Video call to this talk: meet.google.com/qnd-xgva-qyr