Recent progress in metabolic and genetic engineering has greatly improved the efficiency of using lignocellulosic biomass for the production of biofuels and valuable chemicals. Comprising primarily cellulose, hemicellulose, and lignin, lignocellulosic biomass presents considerable challenges for microbial degradation due to its inherent resistance to breakdown. This review discusses the critical role of metabolic engineering in optimizing microbial pathways to increase the yield of lignocellulolytic enzymes, essential for breaking down complex carbohydrates. Engineered microorganisms, including Escherichia coli, Saccharomyces cerevisiae, and Caldicellulosiruptor bescii, have shown promise in improving fermentation efficiency by addressing substrate inhibition and toxicity. Additionally, the engineering of plant cell walls has been explored to enhance polysaccharide accessibility, while lipid engineering has focused on increasing lipid yields from biomass. Techniques such as CRISPR/Cas9, RNA interference, and promoter engineering have enabled precise modifications to enhance enzyme production capabilities. Despite these advancements, challenges such as genetic stability, metabolic burden, and the scale-up of production processes remain. Solutions, including the use of alternative substrates and consolidated bioprocessing, are being investigated to improve the sustainability and cost-effectiveness of biofuel production. This review highlights the significance of ongoing research in metabolic and genetic engineering to fully exploit lignocellulosic biomass, contributing to cleaner and more sustainable energy solutions. By incorporating these advanced strategies, it will be possible to create resilient microbial strains that can effectively transform lignocellulosic biomass into renewable energy and bio-based products.