what is the latest software for my

... for your Mac?

It depends on its exact model.

For macOS itself, please refer to the following:

To learn how to update macOS, please read Keep your Mac up to date - Apple Support

• If there are no updates available, it means your Mac is "up to date" and is already running the latest version of that operating system.

To learn how to upgrade macOS to its latest version, please read How to upgrade to macOS Big Sur

For software in general, you have to investigate each particular software vendor's documentation or support resources.