In this paper, we discuss the concept of Symmetric Teleparallel Gravity and its extensions, mainly focusing on [Formula: see text] modified gravity theories. These theories explore the replacement of the Levi–Civita connection in General Relativity with a general affine connection in flat spacetime, leading to the formulation of gravity based on non-metricity. We highlight the advantages of second-order field equations in [Formula: see text] and [Formula: see text] theories compared to higher-order equations in modified [Formula: see text] gravity. The inclusion of bulk viscosity in the model offers insights into the late-time behavior of the universe. In this regard, we study the spatially homogeneous and anisotropic universe with viscous fluid in the framework of the symmetric teleparallel gravity [Formula: see text]. We solve the field equations and obtain some cosmological parameters, including the deceleration parameter, equation of state parameter, Bulk viscous pressure and scale factor. In the following, we analyze the behavior of the cosmological parameters of the model with some figures and adjust our model parameters with recent data.
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