Question

what will happen if there is no life in the world

Answer 1

Had life not formed so far in Earth, with near perfect positioning of the planet from its star, it's high time chemical reactions start acting and forms the first RNA and the evolution begins.

You would be asking the same question few Billion years later in another social media.

OR in parallel universe

Another life form would be investigating the Earth with its robots analysing why this planet lacks life and they would be surprised by the fact that Earth had a big ocean and water flew from high mountains to the sea.