"The Study of the Unification of Early Inflation and Late-time Acceleration through Dark Energy and Modified Theories of Gravity," I have reported the reconstruction schemes of dark energy models, namely generalized holographic dark energy, modified holographic dark energy, Tsallis holographic dark energy, Barrow holographic dark energy, holographic Ricci dark energy, Nojiri-Odintsov as a specific cut-off of holographic dark energy, Chaplygin gas, Variable generalized Chaplygin gas, modified Chaplygin gas. The scalar fields, such as tachyon, k-essence, dilaton, and DBI-essence, were considered. Our study has focused on unifying early inflation with late-time acceleration. We studied the contribution of Chern-Simons modified gravity, f(Q) gravity, Hořava-Lifshitz gravity, modified f(G) gravity, and f(T) gravity. Most of the reconstructions are carried out using the bulk viscous pressure of the Eckart approach, as it is most consistent with the observational data. Stewart's approach is also used to study one model.