Introduction.- Physics of the Higgs Boson and the Top Quark.- The CMS Experiment at the LHC.- Performance and Optimization of the Level-1 Tau Trigger.- Development of a Level-1 Tau Trigger for the HGCAL Detector in the HL-LHC.- Search for the ttH and tH processes in Multileptonic Final States.- Extraction of the ttH and tH Signals With Machine Learning Techniques.- Extraction of the ttH Signal with the Matrix Element Method.- Conclusions.