The conversion of waste and biomass into energy, fuels, and other valuable resources, with an emphasis on environmental indicators and sustainability goals, is known as valorization. Food crops (starch-rich) and residues (e.g., rice and maize husks), aquatic plants (e.g., algae), lignocellulosic plants (e.g., grass), municipal waste, animal waste, and others are all included in the process of biomass valorization. In modern biorefineries/bioenergy toward a climate-neutral future, biomass valorization for the manufacture of various value-added biochemicals and biofuels plays a vital role. Hydrothermal and biological treatments have been shown to valorize raw biomass materials or upgrade biorefinery intermediate products to provide respectably desired product yields, among the developed valorization approaches for biorefining.