The quest for cleaner alternative sources is all time high and hydrogen (H) has the potential to lead this transition owing to its clean and sustainable make-up. However, the realisation of H as an energy source requires resolving the embrittling phenomenon of H in metals. In this work, we primarily focus on investigating the nano/micro-scale interaction of H with dislocations in iron (Fe) and how their interaction influences the macroscopic dislocation glide behaviour. To this end, we perform molecular static and dynamics simulations using the open-source code LAMMPS on edge dislocations in presence of H. We observe H assisted pinning of dislocations along with solute drag effect dependent on applied stress and temperature. Following this observation, an analytical model is developed to predict the critical resolved shear stress of iron as a function of local H concentration and temperature.