What quicktime player works on the new Catalina download for mac

What quicktime player works on Catalina.

QuickTime 10.5 ships with and works on macOS Catalina 10.15. Prior versions macOS (10.6–10.14) also supported old QuickTime 7 simultaneously with QuickTime 10.x. Only users of QuickTime 7 are affected. File support will be the same for QuickTime 10 users.

Or what app should i use for my security cameras (64 bit)

You don’t mention what file format, protocol or codecs this camera uses.

macOS Catalina requires 64 bit applications. Files can be ordered and chunked in any size that applications will support, 4 bit or 128 bit, whatever suits the needs of the developer; that is not mandated by the operating system.

Now that macOS Catalina doesn’t support 32-bit QuickTime 7, this will also mean that some legacy codecs will not be supported by QuickTime in Catalina. Developers have had time since 2009 to make the transition. However, some of these codecs are still supported by other applications than QuickTime Player.

Users that have used the editing capabilities of QuickTime 7, will have to see if QuickTime 10 offers what they need, or if they need to look at editing tools from other developers.