Understanding the formation and evolution histories of our home Galaxy, the Milky Way, is one of the major outstanding astrophysical problems and provides an opportunity to understand the formation and evolution of galaxies in general. In this talk, I will start with a brief introduction to the evolution history of the Galaxy and move on to our ongoing studies in this regard. I will discuss some of the results from our ongoing work based on a large sample of open star clusters to understand the chemical evolution of the Galaxy. Among all the known chemical elements, lithium is an interesting and useful element for understanding the chemical evolution of the Galaxy. First produced during the well-known Big Bang Nucleosynthesis (BBN), lithium experiences an exciting journey as it evolves through the stars, ISM and galaxies. Even though lithium gets destroyed during most of the life of stars due to its fragile nature, under some circumstances, some evolved giant stars are known to produce Li and contribute towards the Galactic Li enrichment. In one of the studies, we explore the connection of Li enrichment in giants with He-core flash, binarity and strength of He I 10830 \AA\ absorption line. The He-core flash in low-mass giants i.e. the violent onset of He burning in the low-mass giants' core near the RGB tip, is understood to be the primary reason for inducing Li enrichment in giants. I will discuss our ongoing efforts to understand the impact of He-core flash on the star’s atmosphere and chemical composition based on medium-resolution spectra ($\lambda/\Delta\lambda \sim$ 2740) from TANSPEC instrument mounted on 3.6m Devasthal Optical Telescope.