A new mixed ligand complex with metal ion Cu(II) of the type [Cu(II): HL:P] (where HL = 2-Benzimidazolylguanidine and P = Phenanthroline) was synthesized and characterized using (Ft-IR, Mass, electronic, and NMR) analysis, magnetic moment, thermal studies and stoichiometry analysis Job`s method. Mass spectra for [Cu(HL)(P)(CH3COO)2]H2O complex were studied. Also, pH stability for the CuPL chelate was estimated by employing a spectrophotometric analysis. The observed data revealed that (HL and P) ligands behaved as neutral bidentate ligands with NN donation sites. An octahedral geometry for the CuPL complex was proposed based on spectroscopic data. The thermogravimetric study was used to investigate the metal complex temperature stability and deterioration. A theoretical investigation of the Cu(II) complex was performed with the DFT/B3LYP computational method. DFT calculations better understand molecular mechanisms that could not be elucidated experimentally where the energy gaps and other key theoretical parameters were calculated. The vina dock mechanisms and affinities of Cu (II) complexes for (PDB ID: 3cku), (PDB ID: 2vf5), and (PDB ID: 5IJT), receptors were also investigated. The mixed ligand complex was evaluated for antimicrobial and anticancer efficacy against three species of bacteria, fungi, and cancer cell lines. CuPL complex inferred antimicrobials and anticancer activity against the studied organisms which makes them promising drugs.