Title: Calibrating ProtoDUNE-SP detector using cosmogenic muons and towards the first experimental measurement of pion-Argon cross-section in 1-7GeV/c momentum range Abstract: The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber built at the CERN neutrino platform. It serves as a prototype to validate the technology for the first far detector module for the Deep Underground Neutrino Experiment (DUNE) and incorporates full-size components as designed for that module. In addition to its role as a demonstration prototype and engineering test bed for DUNE, the ProtoDUNE-SP TPC was exposed to particle beam which included electrons, protons, pions, kaons with momentum ranging from 0.3 GeV/c to 7 GeV/c. To measure the particle energy loss as it travels through the medium it is important to remove the non-uniformity in detector response and figure out the absolute energy scale to convert the charge into energy. Cosmic ray muons are used to remove the non-uniformity in charge deposition and for the absolute energy scale calibration. The test beam data is being used to measure the hadron-argon cross-section which will be a particularly useful input to various neutrino interaction models of which hadrons are common final state products. I will discuss the detector calibration technique using cosmic-ray muons and the ongoing pion-argon cross-section measurement in the ProtoDUNE-SP experiment.