Descartes’s Meditations on First Philosophy is a classic expression of the GDD, and Descartes’s systematic response to it is ingenious if not entirely compelling. Many versions of the work can be found on the internet.
It is also interesting to work through a modern expression of the GDD in the form of the “Simulation Argument” put forward by Nick Bostrom (available online at https://www.simulation-argument.com/simulation.html). Bostrom is not urging skepticism so much as trying to establish that probably we really are living in a simulation. The basic idea is that if it is possible for simulated beings to be conscious, and if advanced civilizations are likely to run simulations of the universe, then (given the probable populations of such simulated beings) it is more likely than not we are living in a simulation.