This study investigates the potential of Silicon functionalized with gold nanoparticles in sensing major lung cancer biomarkers like Acetone, Toluene and Propanol by utilizing DFT (Density Functional Theory). Silicon functionalized with gold nanoparticles (AuNPs) combines the advantageous properties of both materials, making it highly suitable for sensing applications. Computational tools like VESTA and Quantum Espresso are used to analyze the electronic behavior, bonding characteristics of Si, Si-Au, Si-Au-Acetone, Si-Au-Toluene and Si-Au-Propanol by performing DOS and Band Structure calculations. We observe the Band gap for Si, Si-Au, Si-Au-Acetone, Si-Au-Toluene and Si-Au-Propanol are 0.716eV, 0.19eV, 0.16eV, 0.16eV, 0.17eV. Our study contributes to the understanding of utilizing silicon functionalized gold nanoparticles for sensing application and paving the way for a promising new approach to lung cancer detection.