is there any examples of Sudden resignation or termination of a CEO or other top-level executives

Yes, there have been many examples of sudden resignations or terminations of CEOs and other top-level executives. Here are a few notable ones:

Travis Kalanick, CEO of Uber, resigned in June 2017 following a series of scandals and controversies.
Les Moonves, CEO of CBS, was fired in September 2018 after multiple allegations of sexual harassment and assault.
John Schnatter, founder and CEO of Papa John's, resigned in July 2018 after using a racial slur during a conference call.
Steve Jobs, CEO of Apple, resigned in August 2011 due to health issues. He passed away a few months later.
Ellen DeGeneres, host of The Ellen DeGeneres Show, announced in May 2021 that she would be ending her show after 19 seasons amid allegations of a toxic work environment.
Bob Iger, CEO of Disney, suddenly announced his resignation in February 2020, surprising many in the industry.
Jeffrey Immelt, CEO of General Electric, resigned in June 2017 after the company's stock price declined and investors questioned his leadership