During the Hand-shake process, the Web Server will send the Digital Certificate to the Browser. Web Server will send Digital Certificate along with the Public Key of the Web Server. So, my question here is- what if some hacker steal the Certificate and the Public Key over the internet?Will it cause any harm if the hacker gets the digital certificate and the Public Key of Web Server? Will the hacker starts communicating with the Web Server by pretending as a real client who initiated the hand-shake?

Someone please help me to understand what is gong to happen in this situation. Thank you!