Most films require a huge amount of investment inorder to be successfully completed the film. This budget covers the expense required to make the movie. As there was technological expansion in the world of cinema the budget had a huge increase due to many reasons such as VFX, animation, Hitech cameras, props,etc.
A movie is said to be big budet movie if it invests more than 100$million. They have to sell a huge amount of tickets to atleast to break even the amount.
Most movies that have large CGI effects, visual effects, and ensemble casts have a big budget to cover the costs. Some international movies that come under big budget movies are:
 
Pirates of the Caribbean: On Stranger Tides,Avengers: Age of Ultron, Avengers: Endgame, Avengers: Infinity War, Pirates of the Caribbean: At World's End, Justice League, Solo: A Star Wars Story, Star Wars: The Rise of Skywalker, John Carter, Batman v Superman: Dawn of Justice, Star Wars: The Last Jedi, Tangled, The Lion King, Star Wars: The Force Awakens, Spider-Man 3, Guardians of the Galaxy Vol. 2, Black Panther, Incredibles 2, Fantastic Beasts: The Crimes of Grindelwald, Dark Phoenix, Wonder Woman 1984, Black Widow, Eternals, Spider-Man: No Way Home, etc.
These movies have to spend a minimum of 200 million $ to complete their movies.  Some of them are under franchises such as Marvel Cinematic Universe and certain movie series such as Hobbit, Harry Potter, etc.
Certain  Big Budget Indian movies are:
2.0,Ponniyin Selvan, Adipurush, RRR, The Good Maharaja, Saaho, Radhe Shyam, Thugs of Hindostan, Prithviraj, Mahavir Karna, Brahmāstra, Sye Raa Narasimha Reddy, 83, Tiger Zinda Hai, Baahubali 2: The Conclusion, Pushpa: The Rise, Padmaavat, Zero, Darbar,Indian 2, Baahubali: The Beginning, Marakkar: Arabikadalinte Simham, etc

These movies have marked ₹100 crore (US$13 million) with most movies from bollywood industry.