This study suggests a comprehensive concept for using waste generated from the cashew processing industry in the production of some functional and high-performance bio-composites. Cashew apple bagasse (CAB), cashew nut shell (CNS), and cardanol were used as primary feedstock. Cardanol was used to synthesize cardanol-based benzoxazines that were used as resins. CAB was used to prepare carbon and ash that were used as filler materials in preparing the composites. Thus, three ingredients (resins, carbon, and ash) were obtained, while the CAB and CNS were used directly as feedstock. Firstly, a high-performance CAB-filled panel board composite was prepared as an acoustic barrier, and sound absorption coefficients value of 0.8 at 3000 Hz and 0.7 at 6400 Hz were achieved. Secondly, CNS and CAB were used at different ratios to prepare fuel briquettes, and findings reveal that the briquettes have a calorific value and an ash content of 5225 cal/g and 7%, respectively. Lastly, CAB, carbon, and ash were employed as filler materials in the production of a friction composite, which was found to have a friction coefficient and wear rate of 0.59 and 0.77 × 10−10 cm3/Nm respectively. Overall, this study suggests the concept of zero waste production, as waste from the cashew processing industry was successfully used to produce composite materials for use as acoustic barriers and fuel briquettes. While the ash produced as a waste after using fuel briquettes served as filler material in the production of a robust friction composite.