Microrobot, a tiny, engineered system, often at the microscale, designed to perform multifunctional tasks, which have recently demonstrated considerable promise for enhancing therapeutic and diagnostic biomedical applications. Biohybrid microrobots, relying on biological micro-engines, offer significant advantages over their synthetic counterparts, which can be encumbered by limited fuel availability, restricted access to specific organs and tissues, and potential toxicity. This dissertation will unveil a novel biohybrid microrobot system, detailing its design, fabrication, and in vivo biomedical applications, harnessing the remarkable motility and adaptability of nature’s micro-swimmers, green microalgae. Building on this foundation, the first section will delve into the potential ability of these green algae-based biohybrid microrobots towards biomedical applications. The second section highlights their role in gastrointestinal (GI) system, from delivery routes to treating inflammatory bowel disease (IBD) by combining motile green microalgae with macrophage membrane-coated nanoparticles to efficiently capture pro-inflammatory cytokines 'on-the-fly', successfully modulating disease in a murine IBD model. The third section focuses on using these microrobots as drug carriers to modulate lung system diseases, such as lung metastasis and acute pneumonia, from intratracheal administration to non-invasive inhalation route. Finally, the last section concludes my PhD life’s findings and thinkings, discussing and emphasizing its translational potential for routine clinical applications.