Discovered in 1986, cuprates remain the focus of ongoing research due to their unique superconducting properties, including high transition temperatures (Tc) and critical magnetic fields (Bc). In this thesis, we first explore the potential of using high-Tc superconductors (HTcS) for the fabrication of coplanar waveguide resonators (CPWR). Resonators are essential building blocks of microwave circuits, but their performance is limited by material loss. Using superconductors improves the quality factor of resonators, and HTcS significantly increase their thermal and magnetic operating ranges when compared to their low-Tc counterparts. We report the fabrication of YBa2Cu3O7−δ CPWR resonators and study in detail the different coupling regimes from an overcoupled to an undercoupled one. A high-Q YBa2Cu3O7−δ CPWR is then used to perform electron spin resonance in a cavity on different spin ensembles. In the second part, we investigate the role of dimensionality in the superconducting state of cuprates, focusing on Bi2Sr2CaCu2O8+δ as it can be exfoliated down to one unit cell. Our work includes the fabrication and characterization of Bi2Sr2CaCu2O8+δ ultrathin flakes in both DC and microwave regimes. The DC analysis points towards BKT (Berezinski, Kosterlitz and Thouless) physics, which is confirmed by the jump observed in the microwave superfluid stiffness – a hallmark of the BKT transition. A peak is also measured in the real part of the conductivity, associated with the dissociation of BKT vortex pairs.