These proceedings summarise the results of three major studies of nuclear parton distribution functions (nPDFs) from high-energy collisions at the CERN LHC. The first study examines top-quark-pair production in p+Pb collisions, investigating nPDF modifications at high Bjorken-x. The second study analyses the centrality dependence of dijet yields in p+Pb collisions at root sNN = 8.16 TeV, revealing scaling behaviour with Bjorken-x. The final study presents photon-nuclear production of dijets in ultraperipheral Pb+Pb collisions at root sNN = 5.02 TeV, providing insights into low-x gluon distributions. Collectively, these results enhance the understanding of nPDFs and lay a foundation for future investigations into photonuclear interactions and gluon saturation phenomena.