How can I install Turbo C++ on my Mac with macOS 15.5?

Turbo C++ is ancient and 32-bit. It will not work on macOS 10.15 through Sequoia v15.5, all of which require 64-bit applications. The Apple Command Line Tools for Xcode will install a C/C++/Objective-C/Objective-C++/Swift compiler and a woefully outdated Python 3.9 distribution on Sequoia. All of these are light-years and language standards ahead of Turbo C++.

In the Terminal application, type the following:

xcode-select --install

That does not install Xcode. Your C++ invocation can be:

clang++ -Oz -o foo foo.C [-stdlib=libc++] [-std=c++23]
./foo

In UNIX parlance the square brackets are optional, but if you want to see all of the supported C++ standards you can specify, use -std= and it will list them.

Do you have a copy of Turbo C++? Are you talking about the old DOS version? I learned C++ on that!

I assume there are some MS-DOS emulators for Apple Silicon. I'm sure they run faster than PCs did in real life back in the day.