The production of renewable synthetic fuels and chemicals from solar energy and agricultural waste biomass is considered. Solar thermochemical conversion processes offer a promising pathway to a sustainable fuel economy and green chemical industry. This study investigates the continuous solar-driven gasification of agricultural biomass (betel nut waste) combined with iron oxide (Fe2O3) reduction to produce carbon-neutral syngas and green metallic iron in a single process. A thermodynamic analysis of the system was initially conducted to predict the distribution of equilibrium products. Then, on-sun continuous processing was experimentally carried out under different operating conditions, including betel/Fe$_2$O$_3$ molar ratios (0.56-1.5) and temperatures (900-1200°C) to evaluate the process feasibility and reliability. As a result, solar gasification of betel nut waste combined with Fe$_2$O$_3$ reduction performed exceptionally well with continuous reactant particles feeding, demonstrating a feasible pathway for producing green iron and high-quality syngas. The maximum syngas yield reached 63.3 mmol/gdry_betel, approaching its theoretical value, and high-purity Fe was simultaneously produced. The process demonstrated high efficiency, with maximum carbon conversion approaching 98%, energy upgrade factor up to 1.26, and solarto-fuel energy conversion efficiency up to 14.4%, highlighting remarkable conversion performance of biomass and solar energy to chemicals.