@shantanukumar847 Per your concern about the API key showing up in the error presented to visitors: as you’ve mentioned you can restrict use of the key to your websites only via the HTTP Referrers mechanism in the Google Maps Platform dashboard. In fact, we think you should do this to protect your key.
Catching all error messages reported by Google and removing your key from them may be possible, but it doesn’t guarantee your safety. This type of key is designed for client-side use and it can be retrieved by users inspecting your website.