See all the technical specifications for iMac with the M3 chip and 24-inch display.
https://www.apple.com/au/imac/specs/
Beginning today, the new 15-inch MacBook Air, Mac Studio and Mac Pro powered by Apple silicon are now available.
https://www.apple.com/au/newsroom/2023/06/new-15-inch-macbook-air-mac-studio-and-mac-pro-are-available-today/